Co-reporter:Weijun Kong, Xiaoning Zhao, Qiuju Zhu, Lingfeng Gao, and Hua Cui
Analytical Chemistry July 5, 2017 Volume 89(Issue 13) pp:7145-7145
Publication Date(Web):May 29, 2017
DOI:10.1021/acs.analchem.7b01111
Until now, despite the great success acquired in scientific research and commercial applications, magnetic beads (MBs) have been used for nothing more than a carrier in most cases in bioassays. In this work, highly chemiluminescent magnetic beads containing N-(4-aminobutyl)-N-ethyl isoluminol (ABEI) and Co2+ (Co2+/ABEI/MBs) were first synthesized via a facile strategy. ABEI and Co2+ were grafted onto the surface of carboxylated MBs by virtue of a carboxyl group and electrostatic interaction. The as-prepared Co2+/ABEI/MBs exhibited good paramagnetic properties, satisfactory stability, and intense chemiluminescence (CL) emission when reacted with H2O2, which was more than 150 times that of ABEI functionalized MBs. Furthermore, it was found that 2,4,6-trinitrotoluene (TNT) aptamer could attach to the surface of Co2+/ABEI/MBs via electrostatic interaction and coordination interaction between TNT aptamer and Co2+, leading to a decrease in CL intensity due to the catalytic site Co2+ being blocked by the aptamer. In the presence of TNT, TNT would bind strongly with TNT aptamer and detach from the surface of Co2+/ABEI/MBs, resulting in partial restoration of the CL signal. Accordingly, label-free aptasensor was developed for the determination of TNT in the range of 0.05–25 ng/mL with a detection limit of 17 pg/mL. This work demonstrates that Co2+/ABEI/MBs are easily connected with recognition biomolecules, which are not only magnetic carriers but also direct sensing interfaces with excellent CL activity. It provides a novel CL interface with a magnetic property which easily separates analytes from the sample matrix to construct label-free bioassays.
Co-reporter:Jiangnan Shu, Zhili Han, Tianhua Zheng, Dexin Du, Guizheng Zou, and Hua Cui
Analytical Chemistry December 5, 2017 Volume 89(Issue 23) pp:12636-12636
Publication Date(Web):November 10, 2017
DOI:10.1021/acs.analchem.7b04175
Most electrochemiluminescence (ECL) studies involve single luminophore with a unique emission process, which severely limits its applications. Recently, multicolor ECL has attracted considerable interests. Herein, we report a novel nanoluminophore prepared by coating 5,10,15,20-tetrakis(4-carboxyphenyl)-porphyrin (TCPP) and N-(4-aminobutyl)-N-ethylisoluminol (ABEI) on the surface of TiO2 nanoparticles (TiO2-TCPP-ABEI), which exhibited unique potential-resolved multicolor ECL emissions using H2O2 and K2S2O8 as coreactants in an aqueous solution. Three ECL peaks, ECL-1 at 458 nm, ECL-2 at 686 nm, and ECL-3 at 529 nm, were obtained with peak potentials of 1.05, −1.65, and −1.85 V, which were attributed to the ECL emission of ABEI, TCPP, and TiO2 moiety of the nanoluminophores, respectively. Potential-resolved multicolor ECL from a nanoluminophore was observed for the first time in an aqueous solution. It opens a new research area of multicolor ECL of nanoluminophores, which is of great importance in ECL field from fundamental studies to practical applications.
Co-reporter:Jue Wang, Wenhui Zhong, Xiaoying Liu, Tongtong Yang, Fang Li, Qi Li, Weiren Cheng, Chen Gao, Zheng Jiang, Jun Jiang, and Hua Cui
Analytical Chemistry December 19, 2017 Volume 89(Issue 24) pp:13518-13518
Publication Date(Web):November 23, 2017
DOI:10.1021/acs.analchem.7b03873
Graphene- or graphene oxide (GO)-supported metallic nanoparticles and single metal atom as potentially effective catalysts for chemical reactions have recently received extensive research interests. However, metal utilization in nanoparticle catalysts is limited and metal atoms readily drift on the graphene surface and consequently form aggregated large particles, making practical applications limited. Here, we report metal ions directly immobilized on GO as a novel GO-supported single-ion catalyst for chemiluminecence (CL) reactions. It is found that GO-supported cobalt ions with good stability could catalyze strongly luminol–H2O2 and lucigenin–H2O2 CL reactions, accompanied by dramatically enhanced CL emission. Theoretical studies reveal that the coupling between Co2+ and GO induces effective polarization charges, improving chemical activity of the reaction site, which promotes the generation of intermediate radicals and accelerates the CL reactions. This work may be generalized to other GO-supported metal ions as catalysts for a wide range of chemical reactions. The developed GO-supported cobalt single-ion nanocomposites as nanointerfaces may find future applications in CL bioassays.
Co-reporter:Qi Li;Xiangyang Liu;Meng Zhuang;Xu Wang
RSC Advances (2011-Present) 2017 vol. 7(Issue 59) pp:37261-37267
Publication Date(Web):2017/07/24
DOI:10.1039/C7RA06327J
In this work, we report a novel GO-based hybrid consisting of N-(4-aminobutyl)-N-ethylisoluminol (ABEI), a cobalt(II)-8-hydroxyquinoline-5-sulfonic acid complex (CoII(HQS)2) and reduced GO hybrids (CoII(HQS)2/ABEI/rGO) with good stability and easy purification via a facile strategy by virtue of π–π stacking and coordination, which could be used as an excellent nanocatalytic reaction platform for chemiluminescence (CL) when reacted with hydrogen peroxide, dissolved oxygen and periodate in alkaline solution. This was attributed to the fact that CoII(HQS)2 catalyzed the generation of reactive radicals such as HO˙, O2˙−, and periodate anion radicals (IVI) and π-conjugated carbon radicals (π–CC˙) as well as ABEI˙− on the GO surface. GO as a reaction platform facilitated the reaction of ABEI˙− with O2˙− to produce intensive CL. It was also found that there was a dilution-initiated CL enhancement in CoII(HQS)2/ABEI/rGO–H2O2 system but not in the CoII(HQS)2/ABEI/rGO–O2 and CoII(HQS)2/ABEI/rGO–KIO4 systems. This was due to the competition of the dilution-decreased reduced GO quenching effect and dilution-decreased CoII(HQS)2 concentration. This work provides new insight into the physicochemical properties of functionalized GO hybrids and excellent nanocatalytic platforms for CL reactions, which may find future applications in bioassays, biosensors, bioimaging and microchips.
Co-reporter:Xiangyang Liu;Qi Li;Jiangnan Shu
Journal of Materials Chemistry C 2017 vol. 5(Issue 30) pp:7612-7620
Publication Date(Web):2017/08/03
DOI:10.1039/C7TC02230A
In this study, N-(4-Aminobutyl)-N-ethylisoluminol (ABEI) and CoFe2O4 nanoparticle functionalized graphene hybrids (ABEI/CoFe2O4/GNs) were synthesized for the first time via a hydrothermal reaction and π–π stacking using ABEI as a chemiluminescence (CL) reagent and CoFe2O4 magnetic nanoparticles (MNPs) as a catalyst and magnetic carrier. The as-prepared ABEI/CoFe2O4/GNs demonstrated a good magnetic separation performance, which could be used as a separation tool for the purification of ABEI/CoFe2O4/GNs. Moreover, the as-prepared ABEI/CoFe2O4/GNs exhibited outstanding CL activity and good stability when reacted with H2O2 in alkaline solution; the CL intensity was about 80 times higher than that of ABEI/GNs. The ABEI/CoFe2O4/GNs also exhibited good electrochemiluminescence (ECL) activity in alkaline and near-neutral conditions without any additional co-reactant. The excellent CL/ECL efficiency of the ABEI/CoFe2O4/GNs was attributed to the CoFe2O4 MNPs immobilized on the surface of graphene, which catalyzed the decomposition of H2O2 to generate O2˙− and HO˙, accelerating the CL/ECL reaction. Owing to their good magnetic properties, unique CL/ECL performance and good stability, as well as easy assembly and biocompatibility of graphene, the as-prepared ABEI/CoFe2O4/GNs could be used as an ideal platform for constructing biosensors and bioassays.
Co-reporter:Lingfeng Gao;Li Ju
Journal of Materials Chemistry C 2017 vol. 5(Issue 31) pp:7753-7758
Publication Date(Web):2017/08/10
DOI:10.1039/C7TC01658A
In this work, N-(aminobutyl)-N-(ethylisoluminol) (ABEI) functionalized graphene quantum dots (ABEI-GQDs) with excellent chemiluminescence (CL) and fluorescence (FL) properties were synthesized. Firstly, small 2-dimensional graphene oxide (GO) was prepared by exfoliating and crushing graphite oxide in the presence of HNO3 and KMnO4. Then the size of small 2-dimensional GO was further decreased by reduction with NaBH4 to form GQDs. After that, ABEI was immobilized to the surface of GQDs by simply stirring the mixture of GQDs and ABEI. The synthesized ABEI-GQDs demonstrated excellent CL properties when reacting with H2O2 and wavelength-tunable FL emission with increasing excitation wavelength. And the bright blue FL of ABEI-GQDs could be seen even with the naked eye. Based on their CL and FL properties, a pesticide-sensing array was developed for the differentiation of pesticides. It was found that the sensing strategy could distinguish five pesticides with different concentrations, including thiamethoxam, flubendiamide, dimethoate, dipterex and chlorpyrifos. Novel CL and FL dual-signal graphene quantum dots ABEI-GQDs were obtained for the first time, which may find more applications in bioassays and bioimaging in the future.
Co-reporter:Qi Li, Fang Li, Wen Shen, Xiangyang Liu and Hua Cui
Journal of Materials Chemistry A 2016 vol. 4(Issue 16) pp:3477-3484
Publication Date(Web):21 Mar 2016
DOI:10.1039/C6TC00072J
In this manuscript, lucigenin (Luc) and Co2+ complex bifunctionalized graphene oxide hybrids (Co(Trp)2/Luc/GO) were synthesized via a facile and simple strategy by virtue of π–π stacking and electrostatic interaction. The as-prepared Co(Trp)2/Luc/GO hybrids exhibited good stability, water-solubility and excellent CL activity when reacted with H2O2, which was more than 30 times higher than Luc/GO. The CL mechanism between Co(Trp)2/Luc/GO and H2O2 has been proposed to be due to the fact that Co2+ could facilitate the formation of HO˙, O2˙− and Co2+–HO2−, accelerating lucigenin CL reaction. Moreover, it was also found that ascorbic acid could directly react with Co(Trp)2/Luc/GO to generate CL emission in the presence of dissolved oxygen. By virtue of Co(Trp)2/Luc/GO as a platform, a sensitive, selective, reagent-less and disposable CL sensor for the detection of ascorbic acid was developed. Ascorbic acid could be determined in the range of 5.0 × 10−7–1.0 × 10−3 M with a detection limit of 0.4 μM. This work reveals that catalyst Co(Trp)2 assembled on the surface of Luc/GO exhibits a unique catalytic effect on lucigenin CL reaction, which provides a new strategy for the synthesis of a lucigenin functionalized nanomaterial with high CL efficiency. The synthesized Co(Trp)2/Luc/GO may find more applications in the development of novel analytical methods.
Co-reporter:Zhili Han, Fang Li, Jiangnan Shu, Lingfeng Gao, Xiaoying Liu, and Hua Cui
ACS Applied Materials & Interfaces 2016 Volume 8(Issue 27) pp:17454-17460
Publication Date(Web):June 23, 2016
DOI:10.1021/acsami.6b04055
In this work, three different kinds of acridinium ester (AE)-functionalized carbon nanomaterials, including AE-functionalized carbon nanoparticles (AE-CNPs), AE-functionalized graphene oxide (AE-GO), and AE-functionalized multiwalled carbon nanotubes (AE-MCNTs), were synthesized for the first time via a simple, general, and noncovalent strategy. AE molecules were assembled on the surface of carbon nanomaterials by electrostatic interaction, π–π stacking interaction, and amide bond. The synthesized AE-CNPs, AE-GO, and AE-MCNTs with 5.0 × 10–8 mol·L–1 of synthetic AE concentration, which was very low compared with other chemiluminescence (CL) reagents such as luminol, N-(aminobutyl)-N-(ethylisoluminol), and lucigenin at the concentration of 3.3 × 10–4 to 5.0 × 10–6 mol·L–1 used for the synthesis of CL-functionalized nanomaterials, exhibited outstanding CL activity and good stability. It was found that carbon nanomaterials as nanosized platforms could efficiently immobilize AE molecules and facilitate the formation of OH• and O2•–, leading to strong light emission. Moreover, the CL intensity of AE-GO was the highest, which was about 8.7 and 3.7 times higher than that of AE-CNPs and AE-MCNTs, respectively. This mainly resulted from a difference in the amount of adsorbed AE molecules on the surface of different carbon nanomaterials. Additionally, the prepared AE-CNPs demonstrated excitation-dependent fluorescence property and good fluorescence stability against photobleaching. On the basis of the excellent CL and special fluorescence properties of AE-CNPs, a dual-mode array strategy has been proposed for the first time and seven kinds of transition-metal ions could be successfully discriminated.
Co-reporter:Lingfeng Gao, Li Ju and Hua Cui
RSC Advances 2016 vol. 6(Issue 7) pp:5305-5311
Publication Date(Web):22 Dec 2015
DOI:10.1039/C5RA24928G
The measurement of the binding constant of specific interactions and concentration of a target is of considerable importance in clinical diagnosis, therapy, bioassays and drug design. The development of methods that combine high sensitivity with generalization and simplicity for the measurement of both binding constant and target concentration is highly desirable. Previously, we developed a label-free chemiluminescence (CL) strategy for the measurement of the target concentration and binding constants between DNA aptamers and target simultaneously based on the fact that the target could enhance the CL produced by the reaction of the N-(4-aminobutyl)-N-ethylisoluminol (ABEI) functionalized gold colloid with H2O2. In this study, the enhancement and inhibition effect of various targets on the CL reaction is studied. The generalization of the proposed CL strategy for various targets is also explored. The results demonstrate that the proposed CL strategy is suitable for targets that can cause a change in CL intensity, which includes enhancement and inhibition. It could be applied for the measurement of the dissociation constants of aptamer-binding targets, antibody–antigen complexes, protein-binding small molecules and double-strand DNA hybrids from the millimole to picomole level. It could also be used for the sensitive determination of target concentration, including 2,4,6-trinitrotoluene (TNT), dopamine, tetracycline, human IgG (hIgG), tuberculosis (TB) DNA and mannose, with the detection limit of 0.93 nM–4.1 fM. This strategy is of great potential in fundamental research as well as in applications in life sciences.
Co-reporter:Hongli Zhang, Zhili Han, Xu Wang, Fang Li, Hua Cui, Di Yang, and Zhiping Bian
ACS Applied Materials & Interfaces 2015 Volume 7(Issue 14) pp:7599
Publication Date(Web):March 24, 2015
DOI:10.1021/am509094p
A novel electrochemiluminescence (ECL) immunosensor was developed for the determination of N-terminal pro-brain natriuretic peptide (NT-proBNP) by using N-(aminobutyl)-N-(ethylisoluminol) (ABEI)-functionalized gold nanodots/chitosan/multiwalled carbon nanotubes (ABEI/GNDs/chitosan/COOH-MWCNTs) hybrid as nanointerface. First, ABEI/GNDs/chitosan/COOH-MWCNTs hybrid nanomaterials were grafted onto the surface of ITO electrode via the film-forming property of hybrid nanomaterials. The anti-NT-proBNP antibody was connected to the surface of modified electrode by virtue of amide reaction via glutaraldehyde. The obtained sensing platform showed strong and stable ECL signal. When NT-proBNP was captured by its antibody immobilized on the sensing platform via immunoreaction, the ECL intensity decreased. Direct ECL signal changes were used for the determination of NT-proBNP. The present ECL immunosensor demonstrated a quite wide linear range of 0.01–100 pg/mL. The achieved low detection limit of 3.86 fg/mL was about 3 orders of magnitude lower than that obtained with electrochemistry method reported previously. Because of the simple and fast analysis, high sensitivity and selectivity, and stable and reliable response, the present immunosensor has been successfully applied to quantify NT-proBNP in practical plasma samples. The success of the sensor in this work also confirms that ABEI/GNDs/chitosan/COOH-MWCNTs hybrid is an ideal nanointerface to fabricate a sensing platform. Furthermore, the proposed strategy could be applied in the detection of other clinically important biomarkers.Keywords: carbon nanotube; electrochemiluminescence; label-free immunosensor; N-(aminobutyl)-N-(ethylisoluminol)-functionalized gold nanodot; N-terminal pro-brain natriuretic peptide;
Co-reporter:Xiaoying Liu, Zhili Han, Fang Li, Lingfeng Gao, Gaolin Liang, and Hua Cui
ACS Applied Materials & Interfaces 2015 Volume 7(Issue 33) pp:18283
Publication Date(Web):July 31, 2015
DOI:10.1021/acsami.5b05325
N-aminobutyl-N-ethylisoluminol and horseradish peroxidase bifunctionalized graphene oxide hybrids (ABEI-GO@HRP) were prepared through a facile and green strategy for the first time. The hybrids exhibited excellent chemiluminescence (CL) activity over a wide range of pH from 6.1 to 13.0 when reacted with H2O2, whereas ABEI functionalized GO had no CL emission at neutral pH and showed more than 2 orders of magnitude lower CL intensity than ABEI-GO@HRP at pH 13.0. Such strong CL emission from ABEI-GO@HRP was probably due to that HRP and GO facilitated the formation of O2•–, – CO4•2–, HO•, and π-C═C• in the CL reaction, and GO as a reaction interface promoted the electron transfer of the radical-involved reaction. By virtue of ABEI-GO@HRP as a platform, an ultrasensitive, selective, and reagentless CL sensor was developed for H2O2 detection. The CL sensor exhibited a detection limit of 47 fM at physiological pH, which was more than 2 orders of magnitude lower than previously reported methods. This work reveals that bifunctionalization of GO by ABEI and HRP leads to excellent CL feature and enzyme selectivity, which can be used as an ideal platform for developing novel analytical methods.Keywords: chemiluminescence; graphene oxide; horseradish peroxidase; N-(aminobutyl)-N-(ethylisoluminol); sensor
Co-reporter:Guixin Li, Xiuxia Yu, Danqing Liu, Xiaoying Liu, Fang Li, and Hua Cui
Analytical Chemistry 2015 Volume 87(Issue 21) pp:10976
Publication Date(Web):October 14, 2015
DOI:10.1021/acs.analchem.5b02913
The electrochemiluminescence (ECL) behavior of N-(aminobutyl)-N-(ethylisoluminol)/hemin dual-functionalized graphene hybrids (A-H-GNs) and luminol-functionalized silver/graphene oxide composite (luminol-AgNPs-GO) was investigated under cyclic voltammetry and pulse potential. It was found that A-H-GNs and luminol-AgNPs-GO exhibited excellent ECL activity. On this basis, a label-free ECL aptasensor for 2,4,6-trinitrotoluene (TNT) detection was developed based on bilayer structure of luminescence functionalized graphene hybrids consisting of A-H-GNs and luminol-AgNPs-GO. First, positively charged chitosan-coated A-H-GNs were modified on the surface of indium-doped tin oxide electrode by simple dripping and drying in the air; after that, the modified electrode was immersed in negatively charged luminol-AgNPs-GO modified with aptamer (apta-biotin-SA-luminol-AgNPs-GO) to form apta-biotin-SA-luminol-AgNPs-GO/CS-A-H-GNs/ITO electrode (i.e., aptasensor) by electrostatic interaction. In the presence of TNT, a remarkable decrease in ECL signals was observed due to the formation of aptamer–TNT complex. TNT could be detected based on the inhibition effect. The aptasensor exhibits a wide dynamic range from 1.0 × 10–12 to 1.0 × 10–9 g/mL, with a low detection limit of 6.3 × 10–13 g/mL for the determination of TNT, which is superior to most previously reported bioassays for TNT. Moreover, the proposed aptasensor has been successfully applied to the detection of TNT in environmental water. It is sensitive, selective, and simple, avoiding complicated labeling and purification procedures. Due to the wide target recognition range of aptamer, this strategy provides a promising way to develop new aptasensor for other analytes.
Co-reporter:Jiangnan Shu;Wen Shen
Science China Chemistry 2015 Volume 58( Issue 3) pp:425-432
Publication Date(Web):2015 March
DOI:10.1007/s11426-015-5320-2
The electrochemiluminescence (ECL) behavior of N-(4-aminobutyl)-N-ethylisoluminol (ABEI)-functionalized graphene composite (ABEI-GC) modified on an indium tin oxide (ITO) electrode was studied. ABEI-GC exhibited excellent ECL activity. On this basis, a label-free ECL immunosensor was developed for the sensitive detection of human immunoglobulin G (hIgG) by using ABEI-GC as the ECL nano-interface via a layer-by-layer assembly technique. ABEI-GC was first assembled onto an ITO electrode. Positively charged chitosan was then electrostatically adsorbed to the modified electrode. Finally, negatively charged antibody-coated gold nanoparticles were attached to the surface to form the ECL immunosensor. In the presence of hIgG, hIgG was captured by its antibody. In addition, an ECL signal was detected in the presence of H2O2 when a double potential was applied. The ECL immunosensor for the determination of hIgG showed a linear range of 1.0×10−13–1.0×10−8 g/mL with a detection limit of 5.0×10−14 g/mL. This immunosensor has high sensitivity, wide linearity and good reproducibility. The superior sensitivity of the proposed ECL immunoassay mainly derives from the incorporation of ABEI-GC, which not only improves the ECL intensity, response speed, and stability, but also provides a large specific surface for high levels of protein loading. This work reveals that ABEI-GC is good nano-interface for the construction of ECL biosensors. Our strategy is promising for protein detection and may open up a new avenue for ultrasensitive label-free immunoassays.
Co-reporter:Hongli Zhang and Hua Cui
Nanoscale 2014 vol. 6(Issue 5) pp:2563-2566
Publication Date(Web):20 Dec 2013
DOI:10.1039/C3NR05574D
A one-step strategy was developed for high-density assembly of N-(aminobutyl)-N-(ethylisoluminol) (ABEI) functionalized gold nanodots onto the sidewalls of chitosan-grafted multiwalled carbon nanotubes (cs-MWCNTs) via the reduction of HAuCl4 with ABEI in the presence of cs-MWCNTs, resulting in novel hybrid nanomaterials with excellent chemiluminescence and electrochemiluminescence properties.
Co-reporter:Yi He, Yuting Chen, Chongying Li and Hua Cui
Chemical Communications 2014 vol. 50(Issue 59) pp:7994-7997
Publication Date(Web):01 May 2014
DOI:10.1039/C4CC01242A
A general strategy was developed to fabricate 2-to-1, 4-to-2 and 8-to-3 molecular encoders and a 1-to-2 decoder by assembling graphene oxide with various dye-labeled DNAs.
Co-reporter:Fang Li, Yating Liu, Meng Zhuang, Hongli Zhang, Xiaoying Liu, and Hua Cui
ACS Applied Materials & Interfaces 2014 Volume 6(Issue 20) pp:18104
Publication Date(Web):October 2, 2014
DOI:10.1021/am504985w
In this work, chemiluminescence (CL) reagent and catalyst metal ion complexes bifunctionalized gold nanoparticles (BF-AuNPs) with high CL efficiency were synthesized via an improved synthesis strategy. Biothiols, such as cysteine (Cys), cysteinyl-glycine (Cys-Gly), homocysteine (Hcy), and glutathione (GSH), instead of 2-[bis[2-[carboxymethyl-[2-oxo-2-(2-sulfanylethylamino)ethyl]amino]ethyl]amino]acetic acid (DTDTPA), were used as new chelators. N-(aminobutyl)-N-(ethylisoluminol) (ABEI) was used as a model of CL reagents and Cu2+ as a model of metal ion. In this strategy, biothiols were first grafted on the surface of ABEI-AuNPs by Au–S bond. Then, Cu2+ was captured onto the surface of ABEI-AuNPs by the coordination reaction to form BF-AuNPs. The CL intensity of Cu2+-Cys/ABEI-AuNPs was 1 order of magnitude higher than that of DTDTPA/Cu2+-ABEI-AuNPs synthesized by the previous work. Moreover, strong CL emission of Cu2+-Cys/ABEI-AuNPs was also observed in neutral pH conditions. In addition, the present BF-AuNPs synthesis method exhibited advantages over the previous method in CL efficiency, simplicity, and synthetic rate. Finally, by virtue of Cu2+-Cys/ABEI-AuNPs as a platform, a simple CL chemosensor for the sensitive and selective detection of pyrophosphate ion (PPi) was established based on the competitive coordination interactions of Cu2+ between Cys and PPi. The method exhibited a wide detection range from 10 nM to 100 μM, with a low detection limit of 3.6 nM. The chemosensor was successfully applied to the detection of PPi in human plasma samples. It is of great application potential in clinical analysis. This work reveals that BF-AuNPs could be used as ideal nanointerface for the development of novel analytical methods.Keywords: biothiols; catalyst; chemiluminescence; gold nanoparticles; pyrophosphate ion
Co-reporter:Fang Li, Yuqi Yu, Qi Li, Ming Zhou, and Hua Cui
Analytical Chemistry 2014 Volume 86(Issue 3) pp:1608
Publication Date(Web):January 3, 2014
DOI:10.1021/ac403281g
Tuberculosis (TB) remains one of the leading causes of morbidity and mortality all over the world and multidrug resistance TB (MDR-TB) pose a serious threat to the TB control and represent an increasing public health problem. In this work, we report a homogeneous signal-on electrochemiluminescence (ECL) DNA sensor for the sensitive and specific detection of rpoB genes of MDR-TB by using ruthenium(II) complex functionalized graphene oxide (Ru–GO) as suspension sensing interface and ferrocene-labeled ssDNA (Fc–ssDNA) as ECL intensity controller. The ECL of Ru–GO could be effectively quenched by Fc–ssDNA absorbed on the Ru–GO nanosheets. The Ru–GO has good discrimination ability over ssDNA and dsDNA. Mutant ssDNA target responsible for the drug resistant tuberculosis can hybridize with Fc–ssDNA and release Fc–ssDNA from Ru–GO surface, leading to the recovery of ECL. Mutant ssDNA target can be detected in a range from 0.1 to 100 nM with a detection limit of 0.04 nM. The proposed protocol is sensitive, specific, simple, time-saving and polymerase chain reaction free without complicated immobilization, separation and washing steps, which creates a simple but valuable tool for facilitating fast and accurate detection of disease related specific sequences or gene mutations.
Co-reporter:Mengxiao Liu, Hongli Zhang, Jiangnan Shu, Xiaoyang Liu, Fang Li, and Hua Cui
Analytical Chemistry 2014 Volume 86(Issue 6) pp:2857
Publication Date(Web):March 4, 2014
DOI:10.1021/ac5002433
Despite much progress in functionalized gold nanomaterial (GNMs), chemiluminescent (CL) functionalized GNMs with high CL efficiency are far from fully developed. In this work, we report a general strategy for the synthesis of gold nanoparticles (GNPs) bifunctionalized by CL reagent and catalyst metal complexes (BF-GNPs) by taking N-(aminobutyl)-N-(ethylisoluminol) (ABEI) as a model of CL reagents. The complexes of 2-[bis[2-[carboxymethyl-[2-oxo-2-(2-sulfanylethylamino)ethyl]amino]ethyl]amino]acetic acid (DTDTPA) with various metal ions, including Co2+, Cu2+, Pb2+, Ni2+, Hg2+, Cr3+, Eu3+, La3+, Gd3+, Sm3+, Er3+, Dy3+, Ce4+, and Ce3+, were grafted on the surface of ABEI functionalized GNPs (ABEI-GNPs) to form a series of BF-GNPs. These BF-GNPs exhibited excellent CL activity. In particular, the CL intensity of DTDTPA/Co2+-ABEI-GNPs was over 3 orders of magnitude higher than ABEI-GNPs. This work demonstrates for the first time that metal complexes grafted on the surface of GNPs have unique catalytic activity on the CL reaction, superior to that in the liquid phase. Such BF-GNPs may find future applications in bioassays, microchips, and molecular/cellular imaging.
Co-reporter:Shiyuan Li, Duyu Chen, Qingtong Zhou, Wei Wang, Lingfeng Gao, Jie Jiang, Haojun Liang, Yangzhong Liu, Gaolin Liang, and Hua Cui
Analytical Chemistry 2014 Volume 86(Issue 11) pp:5559
Publication Date(Web):May 14, 2014
DOI:10.1021/ac501061c
Although much effort has been made for studies on aptamer–target interactions due to promising applications of aptamers in biomedical and analytical fields, measurement of the aptamer–target binding constant and binding site still remains challenging. Herein, we report a sensitive label-free chemiluminescence (CL) strategy to determine the target concentration and, more importantly, to measure the target–aptamer binding constant and binding site. This approach is suitable for multiple types of targets, including small molecules, peptides, and proteins that can enhance the CL initiated by N-(aminobutyl)-N-ethylisoluminol functionalized gold colloids, making the present method a general platform to investigate aptamer–target interactions. This approach can achieve extremely high sensitivity with nanogram samples for measuring the target–aptamer binding constant. And the measurement could be rapidly performed using a simple and low-cost CL system. It provides an effective tool for studying the binding of biologically important molecules to nucleic acids and the selection of aptamers. Besides, we have also discovered that the 14-mer aptamer fragment itself split from the ATP-binding aptamer could selectively capture ATP. The binding constant, site, and conformation between ATP and the 14-mer aptamer fragment were obtained using such a novel CL strategy and molecular dynamic simulation.
Co-reporter:Yi He, Xiao He, Xiaoying Liu, Lingfeng Gao, and Hua Cui
Analytical Chemistry 2014 Volume 86(Issue 24) pp:12166
Publication Date(Web):November 25, 2014
DOI:10.1021/ac503123q
It is still a great challenge to develop an array-based sensing system that can obtain only multiparameters, according to a single experiment and device. The role of conventional chemiluminescence (CL) in biosensing has been limited to a signal transducer in which a single signal (CL intensity) can be obtained for quantifying the concentrations of analytes. In this work, we have developed an dynamically tunable CL system, based on the reaction of luminol-functionalized silver nanoparticles (luminol–AgNPs) with H2O2, which could be tunable via adjusting various conditions such as the concentration of H2O2, pH value, and addition of protein. A single experiment operation could obtain multiparameters including CL intensity, the time to appear CL emission and the time to reach CL peak value. The tunable, low-background, and highly reproducible CL system based on luminol–AgNPs is applied, for the first time, as a sensing platform with trichannel properties for protein sensing arrays by principal component analysis. Identification of 35 unknowns demonstrated a success rate of >96%. The developed sensing arrays based on the luminol–AgNPs provide a new way to use nanoparticles-based CL for the fabrication of sensing arrays and hold great promise for biomedical application in the future.
Co-reporter:Xiuxia Yu, Yi He, Jie Jiang, Hua Cui
Analytica Chimica Acta 2014 Volume 812() pp:236-242
Publication Date(Web):17 February 2014
DOI:10.1016/j.aca.2014.01.021
•Novel silver nanoparticles functionalized by luminol are used for the labeling.•The labeling procedure is simple, convenient and fast.•A competitive CL immunoassay has been developed for the detection of CHL.•The immunoassay is simple, fast, sensitive and selective.•It is of application potential for the determination of CHL in foodstuffs.Chloramphenicol (CHL) as a broad-spectrum antibiotic has a broad action spectrum against Gram-positive and Gram-negative bacteria, as well as anaerobes. The use of CHL is strictly restricted in poultry because of its toxic effect. However, CHL is still illegally used in animal farming because of its accessibility and low cost. Therefore, sensitive methods are highly desired for the determination of CHL in foodstuffs. The immunoassays based on labeling as an important tool have been reported for the detection of CHL residues in food-producing animals. However, most of the labeling procedures require multi-step reactions and purifications and thus they are complicated and time-consuming. Recently, in our previous work, luminol functionalized silver nanoparticles have been successfully synthesized, which exhibits higher CL efficiency than luminol functionalized gold nanoparticles. In this work, the new luminol functionalized silver nanoparticles have been used for the labeling of small molecules CHL for the first time and a competitive chemiluminescent immunoassay has been developed for the detection of CHL. Owing to the amplification of silver nanoparticles, high sensitivity for CHL could be achieved with a low detection limit of 7.6 × 10−9 g mL−1 and a wide linear dynamic range of 1.0 × 10−8–1.0 × 10−6 g mL−1. This method has also been successfully applied to determine CHL in milk and honey samples with a good recoveries (92% and 102%, 99% and 107% respectively), indicating that the method is feasible for the determination of CHL in real milk and honey samples. The labeling procedure is simple, convenient and fast, superior to previously reported labeling procedures. The immunoassay is also simple, fast, sensitive and selective. It is of application potential for the determination of CHL in foodstuffs.
Co-reporter:Lingfeng Gao, Hongli Zhang, Hua Cui
Biosensors and Bioelectronics 2014 Volume 57() pp:65-70
Publication Date(Web):15 July 2014
DOI:10.1016/j.bios.2014.01.057
•A general strategy was developed to prepare GO/lucigenin&enzyme biosensors.•The biosensors are homogeneous, reagentless, simple and highly stable.•They are suitable for sensing analytes that produce H2O2 under enzymatic catalysis.In this work, a novel biosensor was developed for the detection of glucose based on glucose oxidase (GOD) functionalized graphene oxide (GO)/lucigenin nanocomposite. In this sensing strategy, GO/lucigenin composite was first prepared by vigorously stirring GO with lucigenin. Then the functionalization of GOD was achieved by simply storing GOD with GO/lucigenin at 4 °C overnight to form GO/lucigenin&GOD composite. When glucose was incubated with GO/lucigenin&GOD composite for 50 min to generate H2O2, followed by the injection of 0.2 M NaOH, CL signal was detected due to the reaction of lucigenin with H2O2. Glucose could be determined in the range of 1.0×10−6–5.0×10−3 g mL−1 with a detection limit of 9.9×10−7 g mL−1. The present biosensor has been successfully applied for the detection of glucose in human serum samples. Compared with previously reported methods, this sensing strategy is homogeneous and reagentless and avoids complicated assembly procedure and pretreatment of serum sample, showing good stability, repeatability, high selectivity and simplicity. Moreover, this strategy has been demonstrated to be a general strategy by replacing GOD with other enzymes such as uricase and choline oxidase for the detection of small molecules such as uric acid and choline. The proposed biosensors may find future applications in the fields such as disease diagnosis and biomedicine.
Co-reporter:Hongli Zhang, Mengxiao Liu, Hua Cui
Journal of Photochemistry and Photobiology A: Chemistry 2014 Volume 275() pp:1-6
Publication Date(Web):1 February 2014
DOI:10.1016/j.jphotochem.2013.10.012
•The FL property of ABEI-AuNPs was studied.•The FL intensity of single ABEI-AuNPs was much brighter than single ABEI molecule.•The ABEI-AuNPs exhibited excellent photostability.•96% FL intensity of ABEI-AuNPs could remain after 5 min continuous excitation.•A novel FRET system was constructed by ABEI-AuNPs and acriflavine.The synthesis of N-(aminobutyl)-N-(ethylisoluminol) (ABEI) functionalized gold nanoparticles (ABEI-AuNPs) and their chemiluminescence properties were described in our previous work. Since the ABEI molecules coated on the surface of ABEI-AuNPs have the fluorescence (FL) activity, the FL property of these ABEI-AuNPs was studied in the present work. It was observed that the FL intensity of a single gold nanoparticle was 634 times brighter than that of one free ABEI molecule, even though 86% of the FL emission of ABEI molecules on the surface of ABEI-AuNPs was inhibited by gold cores through intra- and inter-particle quenching effects. Moreover, the photostability of ABEI-AuNPs was studied and 96% FL intensity of as-prepared ABEI-AuNPs solution remained after 5 min continuous excitation, almost 70% FL intensity remained after 45 min. ABEI-AuNPs exhibited much better resistance to photobleaching property than luminol-AuNPs. Furthermore, ABEI-AuNPs and acriflavine were designed as energy donor and energy acceptor, respectively, to construct a novel fluorescence resonance energy transfer (FRET) system. The efficient energy transfer from ABEI-AuNPs to acriflavine was observed. Taking advantage of excellent labeling property of gold nanomaterials, the FRET behavior between ABEI-AuNPs and acriflavine may find future applications in bioassays based on the FL detection.
Co-reporter:Hongli Zhang, Mengxiao Liu, Guangming Huang, Yuqi Yu, Wen Shen and Hua Cui
Journal of Materials Chemistry A 2013 vol. 1(Issue 7) pp:970-977
Publication Date(Web):23 Nov 2012
DOI:10.1039/C2TB00375A
Herein we report a novel facile synthesis of Au nanopopcorns (AuNPCs) with high chemiluminescent yield by reducing (±)-α-lipoic acid (LA) and HAuCl4 with N-(aminobutyl)-N-(ethylisoluminol) (ABEI) in ethyl alcohol solution at room temperature through a seed growth method. The morphologies of AuNPCs could be changed by adjusting the mole ratios of ABEI, LA and HAuCl4. The characterization results demonstrated that ABEI and the reduction product of LA as stabilizers were coated on the surface of AuNPCs during the synthesis. The AuNPCs, functionalized with ABEI, could react with various oxidants (H2O2, KMnO4, NaClO, Fe(CN)63− and AgNO3) to produce chemiluminescence (CL). The special morphology of AuNPCs maintains the large specific surface area, inherited from its shape and demonstrated excellent catalytic property when involved in CL reaction with H2O2. Thus the CL efficiency of AuNPCs was more than two orders of magnitude higher than that of ABEI functionalized gold nanoparticles in our previous work. The AuNPCs are capable of direct conjugation with protein and DNA while maintaining their luminescent properties, thus they could be potentially useful as a bio-probe for immunoassays and DNA assays.
Co-reporter:Danqing Liu, Guangming Huang, Yuqi Yu, Yi He, Hongli Zhang and Hua Cui
Chemical Communications 2013 vol. 49(Issue 84) pp:9794-9796
Publication Date(Web):23 Aug 2013
DOI:10.1039/C3CC44765K
Herein, we report a facile strategy for the synthesis of dual-functionalized graphene hybrids (A–H–GNs) based on interactions among graphene, N-(aminobutyl)-N-(ethylisoluminol) (ABEI) and hemin. The multilayers of a chemiluminescence reagent (ABEI) and a catalyst (hemin) were accumulated on the graphene surface, resulting in high chemiluminescence performance, good solubility and stability in aqueous solution.
Co-reporter:Yi He, Guangming Huang, and Hua Cui
ACS Applied Materials & Interfaces 2013 Volume 5(Issue 21) pp:11336
Publication Date(Web):October 3, 2013
DOI:10.1021/am404138x
It was found that graphene oxide (GO) could effectively quench the chemiluminescence (CL) emission from a acridinium ester (AE)-hydrogen peroxide system. By taking advantage of this quenching effect, as a proof of concept, a label-free and homogeneous DNA assay was developed for the detection of Mycobacterium tuberculosis DNA. In the absence of target DNA, both probe DNA and AE were absorbed on the surface of GO, producing a weak CL emission owing to the CL quenching effect of GO. However, in the presence of target DNA, a double-stranded structure of DNA was generated, leading to the release of the oligonucleotide from the GO surface. AE favors binding with double-stranded DNA, which will be released from the GO surface; thus, the quenching effect of GO will be no longer effective and a strong CL signal can be observed. This assay can detect M. tuberculosis DNA with a detection limit of 0.65 nM. This sensitivity is lower than that of previously reported electrochemical detection.Keywords: acridinium ester; chemiluminescence; detection; DNA; graphene oxide; label free;
Co-reporter:Yi He, Guangming Huang, Jie Jiang, Qing Zhang, Hua Cui
Carbon 2013 Volume 56() pp:201-207
Publication Date(Web):May 2013
DOI:10.1016/j.carbon.2013.01.024
A simple strategy was developed for the preparation of a graphene oxide (GO) colloid with good water-solubility and stability by the reaction of graphite oxide with nitric acid. The as-prepared GO colloid was characterized by atomic force microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, X-ray diffraction, and Raman spectroscopy. The results demonstrated that the GO colloid had an average height of 0.8 nm, widths in the range ∼10 to 60 nm, and contained abundant carboxyl, and hydroxyl groups. Strong electrochemiluminescent emission was observed from the GO colloid in the presence of K2S2O8. The electrochemiluminescent signal of this system was quite stable with time, and its mechanism was ascribed to the electron-transfer of GO colloid and SO4·- radicals produced by electroreduction of S2O82- ions. The photoluminescent activity of the GO colloid was also studied. The results indicated that it had a visible photoluminescence, excellent photostability, and stable photoluminescence intensity in a wide pH range.
Co-reporter:Jie Jiang, Yi He, Xiuxia Yu, Jinyang Zhao, Hua Cui
Analytica Chimica Acta 2013 Volume 791() pp:60-64
Publication Date(Web):12 August 2013
DOI:10.1016/j.aca.2013.06.048
•It is the first homogeneous aptasensor for interferon-gamma (IFN-γ) detection.•The proposed homogeneous aptasensor enables the facile detection of IFN-γ with high sensitivity, which is comparable with most of previously reported heterogeneous IFN-γ aptasensors.A homogeneous hemin/G-quadruplex DNAzyme (HGDNAzyme) based turn-on chemiluminescence aptasensor for interferon-gamma (IFN-γ) detection is developed, via dynamic in-situ assembly of luminol functionalized gold nanoparticles (lum-AuNPs), DNA, IFN-γ and hemin. The G-quadruplex oligomer of the HGDNAzyme was split into two halves, which was connected with the complementary sequence of P1 (IFN-γ-binding aptamer) to form the oligonucleotide P2. P2 hybridized with IFN-γ-binding aptamer and meanwhile assembled onto lum-AuNPs through biotin–streptavidin specific interaction. When IFN-γ was recognized by aptamer, P2 was released into the solution. The two lateral portions of P2 combined with hemin to yield the catalytic hemin/G-quadruplex DNAzyme, which amplified the luminol oxidation for a turn-on chemiluminescence signaling. Based on this strategy, the homogeneous aptasensor enables the facile detection of IFN-γ in a range of 0.5–100 nM. Moreover, the aptasensor showed high sensitivity (0.4 nM) and satisfactory specificity, pointing to great potential applications in clinical analysis.
Co-reporter:Fang Li, Yuqi Yu, Hua Cui, Di Yang and Zhiping Bian
Analyst 2013 vol. 138(Issue 6) pp:1844-1850
Publication Date(Web):09 Jan 2013
DOI:10.1039/C3AN36805J
A simple and sensitive label-free electrochemiluminescence (ECL) immunosensor based on the use of luminol functionalized gold nanoparticles (luminol-AuNPs) as antibody carriers and sensing platform is described for detecting the acute myocardial infarction biomarker cTnI. The ECL immunosensor was fabricated by the assembly of luminol-AuNPs conjugated with biotinylated antibodies against cTnI (biotin-anti-cTnI-luminol-AuNPs) with the streptavidin coated AuNPs (SA-AuNPs) modified Au electrode directly by virtue of the biotin-SA system. The fabricated sensing platform exhibited stable and strong ECL intensity and could be used for the recognition of target antigen. In the presence of cTnI, a decrease in the ECL intensity was observed. Direct detection of the ECL signal changes during antigen–antibody immunoreactions can be used for the quantification of cTnI. The ECL response exhibited a quite wide dynamic range from 1000 ng mL−1 down to 0.1 ng mL−1. The proposed method has been successfully applied in the detection of cTnI in real plasma samples. This protocol is simple, fast, sensitive, specific, stable and reliable. This work reveals that the luminol-AuNPs are excellent sensing platforms for the fabrication of simple and sensitive immunosensors. Moreover, the proposed strategy may also be extended for the detection of other biomarkers, which is of great application potential in clinical and pharmaceutical analysis.
Co-reporter:Yi He, Hua Cui
Biosensors and Bioelectronics 2013 Volume 47() pp:313-317
Publication Date(Web):15 September 2013
DOI:10.1016/j.bios.2013.03.019
•The first assay based on CRET was developed for detection of histone.•The sensitivity increased 4 orders of magnitude over that of the reported method.•The assay is nonenzymatic, label-free, homogeneous, facile and reliable.AbstractIn this paper, a label free and homogeneous protocol without recognition elements such as antibody or DNA based on nonenzymatic chemiluminescence resonance energy transfer between lucigenin and gold nanoparticles (AuNPs) is developed for the detection of histone. This chemiluminescence resonance energy transfer process originated from a chemiluminescent donor–acceptor pair in which the chemiluminescence system of the lucigenin–H2O2 as a donor and AuNPs as an acceptor owing to the overlapping of the chemiluminescence spectrum of the lucigenin–H2O2 system and the absorption spectrum of AuNPs, leading to a significant decrease in chemiluminescence signal from the lucigenin–H2O2 system. However, the presence of histone resulted in the aggregation of AuNPs via the electrostatic interaction between negatively charged AuNPs and positively charged histone, which inhibited the chemiluminescence resonance energy transfer process. Thus the chemiluminescence signal of the lucigenin–H2O2 system was restored. This could be used for the detection of histone with a linear range of 30–500 ng/mL, and a detection limit of 25 ng/mL. This sensitivity increased about 4 orders of magnitude over that of the reported fluorometric method. The proposed strategy for the detection of histone is simple, facile, reliable, and opens a new avenue for the determination of histone.Graphical abstract
Co-reporter:Yuqi Yu, Qiao Cao, Ming Zhou, Hua Cui
Biosensors and Bioelectronics 2013 Volume 43() pp:137-142
Publication Date(Web):15 May 2013
DOI:10.1016/j.bios.2012.12.018
We report a novel homogeneous label-free aptasensor for 2,4,6-trinitrotoluene (TNT) detection based on an assembly strategy of electrochemiluminescent graphene oxide (GO) with gold nanoparticles (AuNPs) and aptamer. In this sensing strategy, the anti-TNT aptamer was first assembled with AuNPs to form aptamer–AuNPs. Then ruthenium(II) complex functionalized GO (denoted as Ru–GO) was assembled with aptamer–AuNPs by electrostatic interaction. AuNPs could directly quench the electrochemiluminescence (ECL) emission of ruthenium(II) complex on the surface of Ru–GO due to the energy transfer from luminophore to the AuNPs. Weak ECL signal of the assembly was obtained. In the presence of target molecule TNT, the aptamer–AuNPs would aggregate partly due to the aptamer–target interaction and reduce quenching effect, leading to ECL signal restoration and strong ECL signal was obtained. TNT in a range of 0.01–100 ng mL−1 could be detected by use of the ECL intensity discrepancy with a low detection limit of 3.6 pg mL−1. The aptasensor also showed high selectivity towards TNT against 2,4-dinitrotoluene, p-nitrotoluene and nitrobenzene. The present aptasensor has been successfully applied to the detection of TNT in real water samples. Compared with previous reported sensors, this homogenous aptasensor avoided complicated labeling and purification procedure and showed magnificent sensitivity and high selectivity, which made it not only convenient but also time-saving and applicable. Furthermore, this sensing strategy also provides a promising way to develop new ECL aptasensor for other analytes by virtue of other aptamers.Highlights► A sensitive aptasensor for 2,4,6-trinitrotoluene (TNT) detection was constructed. ► It is the first homogeneous label-free sensor based on electrochemiluminescent graphene oxide. ► 0.01–100 ng mL−1 of TNT could be detected with detection limit of 3.6 pg mL−1. ► The aptasensor also show highly selectivity towards TNT.
Co-reporter:Fang Li, Hua Cui
Biosensors and Bioelectronics 2013 Volume 39(Issue 1) pp:261-267
Publication Date(Web):15 January 2013
DOI:10.1016/j.bios.2012.07.060
In the work, a label-free electrochemiluminescence (ECL) aptasensor for the sensitive and selective detection of thrombin was constructed based on target-induced direct ECL signal change by virtue of a novel assembly strategy of oligonucleotide and luminol functionalized gold nanoparticles (luminol-AuNPs). It is the first label-free ECL biosensor based on luminol and its analogs functionalized AuNPs. Streptavidin AuNPs coated with biotinylated DNA capture probe 1 (AuNPs–probe 1) were firstly assembled onto an gold electrode through 1,3-propanedithiol. Then luminol-AuNPs co-loaded with thiolated DNA capture probe 2 and thiolated thrombin binding aptamer (TBA) (luminol-AuNPs–probe 2/TBA) were assembled onto AuNPs–probe 1 modified electrode through the hybridization between capture probes 1 and 2. The luminol-AuNPs–probe 2/TBA acted as both molecule recognition probe and sensing interface. An Au/AuNPs/ds-DNA/luminol-AuNPs/TBA multilayer architecture was obtained. In the presence of target thrombin, TBA on the luminol-AuNPs could capture the thrombin onto the electrode surface, which produced a barrier for electro-transfer and influenced the electro-oxidation reaction of luminol, leading to a decrease in ECL intensity. The change of ECL intensity indirectly reflected the concentration of thrombin. Thus, the approach showed a high sensitivity and a wider linearity for the detection of thrombin in the range of 0.005–50 nM with a detection limit of 1.7 pM. This work reveals that luminol-AuNPs are ideal platform for label-free ECL bioassays.Highlights► This paper introduces a novel label-free electrochemiluminescence aptasensor. ► An assembly strategy of oligonucleotide and luminol funcitionalized AuNPs is showed. ► Thrombin is detected as a model analyte.
Co-reporter:Dr. Yi He ; Hua Cui
Chemistry - A European Journal 2013 Volume 19( Issue 40) pp:13584-13589
Publication Date(Web):
DOI:10.1002/chem.201301782
Abstract
Label-free logic gates (AND, OR, and INHIBIT) based on chemiluminescence (CL) as new optical readout signal have been developed by taking advantage of the unique CL activity of luminol- and lucigenin-functionalized gold nanoparticles/graphene oxide (luminol-lucigenin/AuNPs/GO) nanocomposites. It was found that Fe2+ ions could induce the CL emission of luminol-lucigenin/AuNPs/GO nanocomposites in alkaline solution. On this basis, by using Fe2+ ions and NaOH as the inputs and the CL signal as the output, an AND logic gate was fabricated. When the initial reaction system contained luminol-lucigenin/AuNPs/GO nanocomposites and NaOH, either Fe2+ ions or Ag+ ions could react with the luminol-lucigenin/AuNPs/GO nanocomposites to produce a strong CL emission. This result was used to design an OR logic gate using Fe2+ ions and Ag+ ions as the inputs and CL signal as the output. Moreover, two INHIBIT logic gates for Fe2+ and Ag+ were also developed using by NaClO and L-cysteine as their CL inhibitors, respectively. Furthermore, the proposed logic gates were successfully used to detect Fe2+, Ag+, and L-cysteine, respectively. The developed logic gates may find future applications in sensing, clinical diagnostics, and environmental monitoring.
Co-reporter:Fang Li;Dayong Tian
Luminescence 2013 Volume 28( Issue 1) pp:7-15
Publication Date(Web):
DOI:10.1002/bio.1380
ABSTRACT
Iso-luminol functionalized gold nanomaterials were synthesized in high yield by a simple seeding approach, using the chemiluminescent reagent iso-luminol as reductant in the presence of HAuCl4, AgNO3 and cetyltrimethylammonium bromide (CTAB). The morphology of as-prepared gold nanoparticles was characterized by transmission electron microscopy and UV–vis spectroscopy, showing that gold nanotadpoles (AuNTps) were obtained. Subsequent experiments revealed that the amounts of seed colloids and AgNO3 and the concentrations of iso-luminol and CTAB in the growth solution play critical roles in the formation of well-shaped AuNTps. The surface state of AuNTps was characterized by UV–vis spectroscopy and fluorescence spectroscopy, indicating that iso-luminol and its oxidation product, 4-aminophthalate, coexisted on the surface of AuNTps. The CL behaviour was studied by static injection CL experiments, demonstrating that AuNTps were of CL activity. Finally, the growth mechanism of AuNTps was also discussed. Copyright © 2012 John Wiley & Sons, Ltd.
Co-reporter:Yi He and Hua Cui
Journal of Materials Chemistry A 2012 vol. 22(Issue 18) pp:9086-9091
Publication Date(Web):26 Mar 2012
DOI:10.1039/C2JM16028E
A fast, linker free, one step strategy for in situ preparation of graphene oxide/Ag nanoparticle (GO-AgNP) nano-composites was proposed by reducing AgNO3 with chemiluminescent reagent luminol in the presence of GO. The nano-composites were characterized by transmission electron microscopy, energy-dispersive spectroscopy, X-ray diffraction, UV-Vis absorption spectra, X-ray photoelectron spectroscopy, thermogravimetric analysis, and electrochemical impedance spectroscopy. The results demonstrated that many Ag nanoparticles (AgNPs) with an average diameter of about 22 nm were uniformly dispersed on the surface of GO nanosheets. Luminol molecules were also decorated on the surface of the nano-composites. Thus the nano-composites showed excellent chemiluminescence (CL) activity when reacting with H2O2. Furthermore, the formation mechanism of the as-prepared GO-AgNP nano-composites is proposed as follows: Ag+ adsorbs on the surface of GO via an electrostatic force and Ag+-π orbital interaction. Afterwards, they are in situ gradually reduced by luminol molecules to AgNPs on the surface of GO and some luminol molecules are attached on the surface of the nano-composites. Finally, it was found that glutathione could enhance the CL intensity between GO-AgNP nano-composites and hydrogen peroxide. On this basis, a sensitive and selective method for the detection of glutathione was developed. This method showed a detection limit of 25 μmol L−1 and a linear range from 30 to 1000 μmol L−1. The nano-composites may be attractive and advanced composite materials with great promise as advanced building blocks, CL labels, and platforms for various analytical devices with CL detection such as sensors, microchips and bioassays.
Co-reporter:Jie Jiang, Yi He, Shiyuan Li and Hua Cui
Chemical Communications 2012 vol. 48(Issue 77) pp:9634-9636
Publication Date(Web):09 Aug 2012
DOI:10.1039/C2CC34612E
In this communication, we report a general strategy for the production of carbon nanodots (CDs) by microwave irradiation of amino acids in the presence of acid or alkali. The resultant CDs exhibit strong photoluminescence and intense chemiluminescence enhancement of the NaIO4–H2O2 system.
Co-reporter:Wen Shen, Yuqi Yu, Jiangnan Shu and Hua Cui
Chemical Communications 2012 vol. 48(Issue 23) pp:2894-2896
Publication Date(Web):23 Jan 2012
DOI:10.1039/C2CC17674B
A bottom-up approach for preparing multifunctional graphene-based materials noncovalently functionalized with CL reagents with aromatic rings such as N-(aminobutyl)-N-(ethylisoluminol) (ABEI), luminol and isoluminol is reported. The as-prepared nanocomposites exhibit good CL activity, which may find future applications in analytical, electrochemical and biomedical fields.
Co-reporter:Yuqi Yu, Ming Zhou, Wen Shen, Hongli Zhang, Qiao Cao, Hua Cui
Carbon 2012 Volume 50(Issue 7) pp:2539-2545
Publication Date(Web):June 2012
DOI:10.1016/j.carbon.2012.02.001
We report an approach for the preparation of graphene oxide covalently functionalized with a Ru(II) complex (Ru–GO). A ruthenium(II) complex designed with a long alkyl amino functional group on one of its diimine ligands, bis(2,2′-bipyridine) (N-(2-aminoethyl)-4-(4′-methyl-2,2′-bipyridine-4-yl)butanamide) ruthenium(II), was covalently grafted onto GO by the amide reaction between the amino group of the Ru(II) complex and the carboxyl group of the GO. The as-prepared Ru–GO showed excellent electrochemiluminescence (ECL) activity, good solubility and good stability. Using this hybrid material, a reagent-free ECL method was developed for the detection of tripropylamine to demonstrate the applicability of this new functionalized material. This approach is reliable and highly efficient, and might be extended to other chemiluminescent molecules containing an amino group such as luminol and its analogues to functionalize GO with ECL activity.
Co-reporter:Ying Chai, Dayong Tian, Hua Cui
Analytica Chimica Acta 2012 Volume 715() pp:86-92
Publication Date(Web):17 February 2012
DOI:10.1016/j.aca.2011.12.006
An electrochemiluminescence (ECL) biosensor for simultaneous detection of adenosine and thrombin in one sample based on bifunctional aptamer and N-(aminobutyl)-N-(ethylisoluminol) functionalized gold nanoparticles (ABEI-AuNPs) was developed. A streptavidin coated gold nanoparticles modified electrode was utilized to immobilize biotinylated bifunctional aptamer (ATA), which consisted of adenosine and thrombin aptamer. The ATA performed as recognition element of capture probe. For adenosine detection, ABEI-AuNPs labeled hybridization probe with a partial complementary sequence of ATA reacted with ATA, leading to a strong ECL response of N-(aminobutyl)-N-(ethylisoluminol) enriched on ABEI-AuNPs. After recognition of adenosine, the hybridization probe was displaced by adenosine and ECL signal declined. The decrease of ECL signal was in proportion to the concentration of adenosine over the range of 5.0 × 10−12–5.0 × 10−9 M with a detection limit of 2.2 × 10−12 M. For thrombin detection, thrombin was assembled on ATA modified electrode via aptamer–target recognition, another aptamer of thrombin tagged with ABEI-AuNPs was bounded to another reactive site of thrombin, producing ECL signals. The ECL intensity was linearly with the concentration of thrombin from 5 × 10−14 M to 5 × 10−10 M with a detection limit of 1.2 × 10−14 M. In the ECL biosensor, adenosine and thrombin can be detected when they coexisted in one sample and a multi-analytes assay was established. The sensitivity of the present biosensor is superior to most available aptasensors for adenosine and thrombin. The biosensor also showed good selectivity towards the targets. Being challenged in real plasma sample, the biosensor was confirmed to be a good prospect for multi-analytes assay of small molecules and proteins in biological samples.Graphical abstractHighlights► A novel ECL biosensor based on bifunctional aptamer and ABEI-AuNPs. ► A good prospect for multi-analyte assay of small molecule and protein in biological sample. ► The sensitivity of the sensor is superior to most available aptasensors for adenosine and thrombin. ► The bifunctional aptamer was for the first time applied to ECL biosensor.
Co-reporter:Xiuxia Yu, Ying Chai, Jie Jiang, Hua Cui
Journal of Photochemistry and Photobiology A: Chemistry 2012 Volume 241() pp:45-51
Publication Date(Web):1 August 2012
DOI:10.1016/j.jphotochem.2012.04.023
Co-reporter:Yi He and Hua Cui
The Journal of Physical Chemistry C 2012 Volume 116(Issue 23) pp:12953-12957
Publication Date(Web):May 22, 2012
DOI:10.1021/jp303304z
A facile, fast, and reliable method was proposed to prepare luminol and lucigenin bifunctionalized AuNPs/GO nanocomposites via absorption of AuCl4– by positively charged lucigenin functionalized GO and the subsequent reduction of AuCl4– by luminol at room temperature for the first time. The morphology and surface composition of the nanocomposites were characterized by transmission electron microscopy, X-ray powder diffraction, and mass and fluorescence spectra. The results indicated that AuNPs with a uniform size are fairly well monodispersed on the surface of GO. The size of AuNPs in the nanocomposites was tunable from 8 to 18 nm by changing the amount of AuCl4–. Moreover, it was found that luminol and lucigenin coexisted on the surface of the nanocomposites. A formation mechanism of AuNPs/GO nanocomposites is proposed. It is suggested that lucigenin molecules and AuNPs were located at the surface of GO by π–π stacking and electrostatic force respectively, and luminol existed on the surface of AuNPs by virtue of Au–N covalent interaction in the as-prepared nanocomposites. Because luminol and lucigenin were attached to the surface of the nanocomposites, the obtained nanocomposites could react with hydrogen peroxide resulting in a good dual-wavelength chemiluminescence activity. Also, the nanocomposites could also react with silver nitrate giving rise to chemiluminescence emission. Besides, the nanocomposites exhibited fluorescence properties. The nanocomposites could be considered as not only functionalized materials but also as a promising platform for multipurpose sensing and bioassays.
Co-reporter:Dr. Yi He ; Hua Cui
Chemistry - A European Journal 2012 Volume 18( Issue 16) pp:4823-4826
Publication Date(Web):
DOI:10.1002/chem.201104044
Co-reporter:Yuqi Yu, Ming Zhou and Hua Cui
Journal of Materials Chemistry A 2011 vol. 21(Issue 34) pp:12622-12625
Publication Date(Web):25 Jul 2011
DOI:10.1039/C1JM11843A
Bis(2,2′-bipyridine)(5-amino-1,10-phenanthroline) ruthenium(II) functionalized gold nanoparticles with electrochemiluminescence activity were successfully synthesized by a simple one-pot method via the reduction of HAuCl4 with NaBH4 in the presence of bis(2,2′-bipyridine)(5-amino-1,10-phenanthroline) ruthenium(II), which is of great potential for application in bioanalysis.
Co-reporter:Dayong Tian, Hongli Zhang, Ying Chai and Hua Cui
Chemical Communications 2011 vol. 47(Issue 17) pp:4959-4961
Publication Date(Web):22 Mar 2011
DOI:10.1039/C1CC10435G
A novel strategy for the synthesis of CF-AuNMs by reducing HAuCl4 with ABEI in aqueous solution at room temperature is reported. No additional stabilizing and reducing reagents are needed, and various morphologies of CF-AuNMs can be obtained. It could be used as bio-probe for bioassays.
Co-reporter:Yi He, Danqing Liu, Xinyuan He and Hua Cui
Chemical Communications 2011 vol. 47(Issue 38) pp:10692-10694
Publication Date(Web):05 Sep 2011
DOI:10.1039/C1CC14389A
A novel one-pot method for the synthesis of chemiluminescence functionalized AgNPs has been reported and an ECL sensor has been developed for the detection ofM. tuberculosisDNA.
Co-reporter:Ying Chai, Dayong Tian, Jie Gu and Hua Cui
Analyst 2011 vol. 136(Issue 16) pp:3244-3251
Publication Date(Web):09 Jun 2011
DOI:10.1039/C1AN15298J
A novel electrochemiluminescence (ECL) aptasensor for platelet-derived growth factor B chain (PDGF-BB) assay was developed by assembling N-(aminobutyl)-N-ethylisoluminol functionalized gold nanoparticles (ABEI-AuNPs) with aptamers as nanoprobes. In the protocol, the biotinylated aptamer capture probes were first immobilized on a streptavidin coated gold nanoparticle (AuNPs) modified electrode, afterwards, the target PDGF-BB and the ABEI-AuNPs tagged aptamer signal probe were successively attached to the modified electrode by virtue of the dimer structure of PDGF-BB to fabricate a “sandwich” conjugate modified electrode, i.e. an aptasensor. ECL measurement was carried out with a double-step potential in carbonate buffer solution containing H2O2. The aptasensor showed high sensitivity and selectivity toward PDGF-BB and specificity toward PDGF-BB aptamer. The detection limit was as low as 2.7 × 10−14 M. In this work, the ABEI-AuNPs synthesized by a simple seed growth method have been successfully used as aptamer labels, which greatly amplified the ECL signal by binding numbers of ABEI molecules on the surface of AuNPs. The ABEI-AuNPs signal amplification is superior to other reported signal amplification strategies based on aptamer-related polymerase chain reaction or functionalized nanoparticles in simplicity, stability, labeling property and practical applicability. And the ABEI-AuNPs based nanoprobe is more sensitive than the luminol functionalized AuNPs based nanoprobe. Moreover, such an ultra-sensitive and low-cost assay can be accomplished with a simple and fast procedure by using a simple ECL instrumentation. The aptasensor was also applied for the detection of PDGF-BB in human serum samples, showing great application potential. Given these advantages, the ECL aptasensor is well suited for the direct, sensitive and rapid detection of protein in complex clinical samples.
Co-reporter:Jie Jiang, Ying Chai and Hua Cui
RSC Advances 2011 vol. 1(Issue 2) pp:247-254
Publication Date(Web):02 Aug 2011
DOI:10.1039/C1RA00206F
A novel electrogenerated chemiluminescence (ECL) DNA sensor was developed for a fast test for Mycobacterium tuberculosis (MTB) without using the polymerase chain reaction amplification, and was based on luminol functionalized gold nanoprobes with excellent signal amplification functionality. This nanoprobe was formed by the conjugation of luminol functionalized gold nanoparticles (lum–AuNPs) with signal DNA probes. An 81bp segment derived from the Mycobacterium tuberculosis specific insertion sequence IS6110 was chosen as the target strand and corresponding probes were designed to specifically hybridize with it. Biotinylated capture probes can be effectively immobilized directly on a streptavidin coated AuNP modified indium tin oxide electrode. After catching the TB target strand, signal probes tagged with lum–AuNPs were attached to the assembled electrode surface to form a sandwich-type TB sensor. Treating the resulting electrode surface with a carbonate buffer solution containing 1.0 mmol L−1 of H2O2 and applying a double-step potential to the electrode, the ECL response was generated which realized the detection of the TB target strand. The detection limit was estimated to be 6.7 × 10−15 mol L−1 (equal to approximately 1.7 × 10−10 g L−1) of the synthetic TB target strand, which is superior to other genetic methodologies for TB tests based on gold nanoprobes. Genomic DNA from other pathogenic bacterias (Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus) had a negligible effect on its detection, which guaranteed the good selectivity of the TB sensor. The efficacy of the TB sensor was also evaluated for genomic DNA extracted from cultured M. tuberculosis. The TB sensor is sensitive, highly selective, convenient and cost-effective. The simplicity of the assay and the lack of a requirement for sophisticated equipment render the TB sensor a promising candidate as a rapid molecular test for the detection ofM. tuberculosis.
Co-reporter:Yi He;Hao Zhang;Ying Chai
Analytical and Bioanalytical Chemistry 2011 Volume 399( Issue 10) pp:3451-3458
Publication Date(Web):2011 April
DOI:10.1007/s00216-010-4157-y
It was found that tripropylamine (TPA) could be used as a coreactant to initiate the electrochemiluminescence (ECL) of acridinium NHS ester (AE NHS) labels attached to DNA. The radicals generated in the electro-oxidation process of TPA reacted with AE NHS to form the excited N-methylacridone, giving rise to light emission. The AE/TPA ECL system was for the first time used as the detection system for developing an ECL-based DNA sensor. In the protocol, streptavidin-modified gold nanoparticles were firstly immobilized onto a thiol-treated gold electrode. The streptavidin could specifically interact with the biontinylated capture DNA. Afterwards, the target DNA and the AE-labeled report DNA were conjugated onto the electrode step by step due to the hybridization reactions, and a sandwich-type sensor was fabricated. The ECL signals of the sensor were obtained under pulse potential condition in alkaline solution containing 50.0 mmol L−1 TPA. Under optimized experimental conditions, the linear range of the DNA sensor for the determination of the target DNA was from 5.0 × 10−15 to 5.0 × 10−12 mol L−1. The detection limit (S/N = 3) was 3.0 × 10−15 mol L−1. Moreover, the sensor could specifically recognize the target DNA against one base-pair mismatched sequences, two base-pair mismatched sequences, and the noncomplementary sequences. It is of great application potential in clinic analysis.
Co-reporter:Wen Shen, Dayong Tian, Hua Cui, Di Yang, Zhiping Bian
Biosensors and Bioelectronics 2011 Volume 27(Issue 1) pp:18-24
Publication Date(Web):15 September 2011
DOI:10.1016/j.bios.2011.05.022
A novel nanoparticle-based electrochemiluminescence (ECL) immunosensor was designed for highly sensitive and selective detection of human cardiac troponin I (cTnI), an important Acute Myocardial Infarction (AMI)-related biomarker, by using N-(aminobutyl)-N-(ethylisoluminol)-functionalized gold nanoparticles (ABEI-AuNPs) as labels. ABEI-AuNPs were successfully synthesized via a simple seed growth method. A great number of luminescence molecules ABEI as stabilizers were coated on the surface of the AuNPs, which exhibited better ECL activities than previously reported luminol functionalized gold nanoparticles. ABEI-AuNPs were used as new ECL labels to build bio-probes by conjugation with secondary antibodies, which showed good ECL activity, immunological activity, and stability. Another kind of AuNPs functionalized with streptavidin was modified on the electrode surface for biotinylated antibodies capture through the specific interaction of biotin/streptavidin and enhancing the electrical connectivity. By combining with the novel ECL labels and amplification of AuNPs and biotin–streptavidin system, a high sensitive sandwich-type electrochemiluminescence immunoassay was developed for detecting human cTnI with a low detection limit of 2 pg/mL. The immunosensor showed good precision, acceptable stability and reproducibility and could be used for the detection of cTnI in real samples, which was of great potential application in clinical analysis. Importantly, the sensitive detection would have far more diagnostic value than would absolute measurements during the early stage of AMI.
Co-reporter:Bo Liu, Yi He, Chunfeng Duan, Na Li, Hua Cui
Journal of Photochemistry and Photobiology A: Chemistry 2011 Volume 217(Issue 1) pp:62-67
Publication Date(Web):1 January 2011
DOI:10.1016/j.jphotochem.2010.09.019
It was found that lucigenin alkaline solution could react with hydrazine in the presence of Pt nanoparticles to generate strong chemiluminescence (CL) centered at 480 nm. In order to explore the CL mechanism, UV–visible spectra, X-ray photoelectron spectra studies before and after the CL reaction were carried out. The effects of O2 and superoxide dismutase (SOD) on the CL reaction were examined. The catalytic effect of Pt NPs on the hydrazine–O2 reaction was studied. A possible mechanism is proposed to be due to that Pt NPs catalyzed the reaction between hydrazine and the dissolved oxygen under alkaline conditions to yield hydroperoxide species and superoxide radical anion, which further oxidized lucigenin to produce CL emission. Moreover, the effects of some organic compounds containing hydroxyl (OH), carboxyl (COOH), carbonyl (CO), amino (NH2), or sulfur groups on the lucigenin–hydrazine–Pt NPs CL system were tested. Thiol-containing compounds such as cysteine (Cys), glutathione (GSH), homocysteine (Hcy), and 6-mercaptopurine (6-MP) were observed to greatly enhance the CL intensity. It is suggested that the CL enhancement might be due to the fact that thiol-containing compounds could facilitate the electron transfer process under the catalysis of Pt nanoparticles and accelerate the generation of OH and O2− radicals, leading to the strong CL.
Co-reporter:Na Li, Wei Wang, Dayong Tian and Hua Cui
Chemical Communications 2010 vol. 46(Issue 9) pp:1520-1522
Publication Date(Web):15 Jan 2010
DOI:10.1039/B920736H
Luminol could react with acidic Pd–Ag colloid to yield a novel chemiluminescence, which could be reversibly controlled by the pH of Pd–Ag colloid. This offers a novel way to design smart nanomaterials with pH-controlled catalysis.
Co-reporter:Ying Chai, Dayong Tian, Wei Wang and Hua Cui
Chemical Communications 2010 vol. 46(Issue 40) pp:7560-7562
Publication Date(Web):17 Sep 2010
DOI:10.1039/C0CC02356F
Luminol functionalized gold nanoparticles were used as labels for electrochemiluminescence signal amplification and an ultrasensitive, highly selective, convenient, low cost DNA detection strategy was developed.
Co-reporter:Dayong Tian, Chunfeng Duan, Wei Wang, Hua Cui
Biosensors and Bioelectronics 2010 Volume 25(Issue 10) pp:2290-2295
Publication Date(Web):15 June 2010
DOI:10.1016/j.bios.2010.03.014
An ultrasensitive electrochemiluminescence (ECL) immunosensor based on luminol functionalized gold nanoparticle (AuNP) labeling was developed using human immunoglobulin G (hIgG) as a model analyte. The primary antibody biotin-conjugated goat-anti-human IgG was first immobilized on a streptavidin coated AuNP modified electrode, then the antigen (human IgG) and the luminol functionalized AuNP-labeled second antibody were conjugated successively to form a sandwich-type immunocomplex, i.e. immunosensor. ECL was carried out with a double-step potential in carbonate buffer solution containing 1.0 mmol/L H2O2. Since thousand of luminol molecules were coated on the surface of AuNPs to realize labeling of multiple molecules with CL activity at a single antibody and the amplification of AuNPs and biotin–streptavidin system was utilized, luminol ECL signal could be enhanced greatly, finally resulting in extremely high sensitivity. The ECL method shows a detection limit of 1.0 pg/mL (S/N = 3) for hIgG, which is superior to all previously reported methods for the determination of hIgG. Moreover, the proposed method is also simple, stable, specific, and time-saving, avoiding the complicated stripping procedure during CL detection and the uncontrollable synthesis of irregular nanoparticles compared with other chemiluminescence immunoassay based on AuNP labeling. Additionally, the labeling procedure is also superior to that of other reported multilabeling strategies, such as Ru complex-encapsulated polymer microspheres, and most of Ru complex-encapsulated liposomes in simplicity, stability, labeling property and practical applicability. Finally, the proposed method has been successfully applied to the detection of hIgG in human serums.
Co-reporter:Na Li, Jie Gu, Hua Cui
Journal of Photochemistry and Photobiology A: Chemistry 2010 Volume 215(2–3) pp:185-190
Publication Date(Web):25 September 2010
DOI:10.1016/j.jphotochem.2010.08.016
It was found that silver nanoparticles (NPs) in the presence of nucleophiles and Cu2+ could induce luminol to produce chemiluminescence (CL). The AgNPs–NaBr–CuSO4–luminol system was chosen as a model system to study the CL mechanism. UV–vis absorption spectra showed that silver nanoparticles in the presence of NaBr could react with CuSO4 before injection of luminol. The X-ray diffraction patterns and X-ray photoelectron spectra demonstrated that Cu(I) complex was a key reaction product in AgNPs–NaBr–CuSO4 system. Besides, it was also found that superoxide dismutase could inhibit the CL, revealing that a superoxide anion was involved in the CL reaction. On this basis, it was suggested that the luminol CL induced by silver nanoparticles in the presence of NaBr and Cu2+ derived from Cu(I) complex formed via the reduction of CuSO4 by AgNPs by the aid of NaBr, which reacted with the dissolved oxygen to generate the superoxide anion; then the superoxide anion reacted with luminol to produce CL. Br− as a nucleophile was considered to decrease the oxidation potential of silver nanoparticles so that Cu(II) is readily reduced to Cu(I) and to bind to Cu(I) preventing Cu(I) from dismutation in water. As expected, other nucleophiles such as Cl−, I− and thiosulfate, which were also efficient to decrease the oxidation potential of AgNPs and bind to Cu(I), could also induce the luminol CL.
Co-reporter:Chun-Feng Duan and Hua Cui
Chemical Communications 2009 (Issue 18) pp:2574-2576
Publication Date(Web):26 Mar 2009
DOI:10.1039/B901232J
Ethanol can initiate Pt nanoparticles to catalyze the chemiluminescent reaction of alkaline lucigenin solution, leading to a visible light emission with autocatalytic property.
Co-reporter:Na Li, Jizhao Guo, Bo Liu, Yuqi Yu, Hua Cui, Lanqun Mao, Yuqing Lin
Analytica Chimica Acta 2009 Volume 645(1–2) pp:48-55
Publication Date(Web):10 July 2009
DOI:10.1016/j.aca.2009.04.050
Our previous work showed that gold nanoparticles could trigger chemiluminescence (CL) between luminol and AgNO3. In the present work, the effect of some biologically important reductive compounds, including monoamine neurotransmitters and their metabolites, reductive amino acids, ascorbic acid, uric acid, and glutathione, on the novel CL reaction were investigated for analytical purpose. It was found that all of them could inhibit the CL from the luminol–AgNO3–Au colloid system. Among them, monoamine neurotransmitters and their metabolites exhibited strong inhibition effect. Taking dopamine as a model compound, the CL mechanism was studied by measuring absorption spectra during the CL reaction and the reaction kinetics via stopped-flow technique. The CL inhibition mechanism is proposed to be due to that these tested compounds competed with luminol for AgNO3 to inhibit the formation of luminol radicals and to accelerate deposition of Ag atoms on surface of gold nanoparticles, leading to a decrease in CL intensity. Based on the inhibited CL, a novel method for simultaneous determination of monoamine neurotransmitters and their metabolites was developed by coupling high-performance liquid chromatography with this CL reaction. The new method was successfully applied to determine the compounds in a mouse brain microdialysate. Compared with the reported HPLC–CL methods, the proposed method is simple, fast, and could determine more analytes. Moreover, the limits of linear ranges for NE, E, and DA using the proposed method were one order of magnitude lower than the luminol system without gold nanoparticles.
Co-reporter:Hao Zhang and Hua Cui
Langmuir 2009 Volume 25(Issue 5) pp:2604-2612
Publication Date(Web):February 4, 2009
DOI:10.1021/la803347h
Carboxylic acid- and amino-functionalized ionic liquids were used as the stabilizer for the systhesis of metal nanoparticles in aqueous solution. Smaller gold nanoparticles (3.5 nm) and platinum nanoparticles (2.5 nm) were prepared with NaBH4 as the reductant. Larger gold nanospheres (23, 42, and 98 nm) were synthesized using different quantities of trisodiumcitrate reductant. The morphology and the surface state of the metal nanoparticles were characterized by high-resolution transmission electron microscopy, UV−visible spectroscopy, and X-ray photoelectron spectroscopy. X-ray photoelectron spectroscopy spectra indicated that binding energies of C 1s and N 1s from ionic liquids on the surface of metal nanoparticles shifted negatively compared with that from pure ionic liquids. The mechanism of stabilization is proposed to be due to the interactions between imidazolium ions/functional groups in ionic liquids and metal atoms. Resonance Rayleigh scattering property of the functionalized ionic liquid-stabilized metal nanoparticles was also explored. It was found that amino-functionalized ionic liquid-stabilized gold nanoparticles exhibited lower resonance Rayleigh scattering intensity than trisodiumcitrate stabilized gold nanoparticles, which is expected to decrease the background of the resonance Rayleigh scattering intensity in the determination of various analytes. Moreover, it was found that all the as-prepared metal nanoparticles could be easily assembled on the multiwalled carbon nanotubes, which was confirmed by high-resolution transmission electron microscopy and energy dispersive X-ray spectroscopy. In this case, ionic liquids acted as a linker to connect metal nanoparticles with carbon nanotubes. The imidazolium ring moiety of ionic liquids might interact with the π-electronic nanotube surface by virtue of cation−π and/or π−π interactions, and the functionalized group moiety of ionic liquids might interact with the metal NPs surface. Finally, it was observed that plantinum nanoparticle/multiwalled carbon nanotube hybrids could be well dispersed in water, which may find future applications in fields such as catalysis, nanoscale electronics, as well as sensors.
Co-reporter:Dayong Tian, Chunfeng Duan, Wei Wang, Na Li, Hao Zhang, Hua Cui, Yingyu Lu
Talanta 2009 Volume 78(Issue 2) pp:399-404
Publication Date(Web):30 April 2009
DOI:10.1016/j.talanta.2008.11.037
A novel electrochemiluminescence (ECL) sandwich-type immunosensor for human immunoglobulin G (hIgG) on a gold nanoparticle modified electrode was developed by using N-(aminobutyl)-N-ethylisoluminol (ABEI) labeling. The primary antibody, goat-anti-human IgG was first immobilized on a gold nanoparticle modified electrode, then the antigen (human IgG) and the ABEI-labeled second antibody was conjugated successively to form a sandwich-type immunocomplex. ECL was carried out with a double-step potential in carbonate buffer solution (CBS) containing 1.5 mM H2O2. The ECL intensity increased linearly with the concentration of hIgG over the range 5.0–100 ng/mL. The limit of detection was 1.68 ng/mL (S/N = 3). The relative standard deviation was 3.79% at 60 ng/mL (n = 9). The present immunosensor is simple and sensitive. It has been successfully applied to the detection of hIgG in human serums.
Co-reporter:ChunFeng Duan;GuangMing Liu;ZhiFeng Zhang
Science Bulletin 2009 Volume 54( Issue 11) pp:1901-1907
Publication Date(Web):2009 June
DOI:10.1007/s11434-009-0245-9
It was found that rhodamine B could induce oscillating chemiluminescence (OCL) from the Ce4+-catalyzed Belousov-Zhabotinsky reaction. This new OCL system, i.e., rhodamine B-malonic acid-bromate-Ce(IV)-sulfuric acid, exhibited two clearly distinguished emission peaks in each oscillation period. The initial concentrations of the reactants strongly influenced the oscillation pattern. For the study of the CL mechanism, a platform for a versatile and simultaneous potential and CL measurement was established to compare the potential oscillation with the CL oscillation behavior of this system. The CL spectra, UV-visible absorption spectra and time-resolved fluorescence spectra of this OCL system were studied. A possible, simplified mechanism for the OCL is proposed. It is suggested that the generation of the two CL peaks is likely due to the oxidation of the intermediate of rhodamine B by Ce(IV) and Br2, respectively. This work provided a new method and platform to research the complex chemical oscillations.
Co-reporter:Chun-Feng Duan, Yu-Qi Yu and Hua Cui
Analyst 2008 vol. 133(Issue 9) pp:1250-1255
Publication Date(Web):28 Jul 2008
DOI:10.1039/B807163B
A novel microplate-compatible chemiluminescence (CL) immunoassay has been developed for the determination of human immunoglobulin G (IgG) based on the luminol–AgNO3–gold nanoparticles CL system. Polystyrene microtiter plates were used for both immunoreactions and CL measurements. The primary antibody, goat-anti-human IgG, was first immobilized on polystyrene microwells. Then the antigen (human IgG) and the gold-labeled second antibody were connected to the microwells successively to form a sandwich-type immunocomplex. The gold label could trigger the reaction between luminol and AgNO3, accompanied by light emission. Under the optimized conditions, the CL intensity of the system was linear with the logarithm of the concentration of human IgG in the range from 25 to 5000 ng mL−1, with a detection limit of 12.8 ng mL−1 (∼80 pM) at a signal to noise ratio of three (S/N = 3). Compared with other reported CL immunoassay method based on gold labels, the proposed CL protocol avoids a strict stripping procedure or difficult to control synthesis processes, making the method more simple, time-saving and easily automated. The present CL method is promising for the determination of clinically important bioactive analytes.
Co-reporter:Wei Wang, Hua Cui, Zhao-Xiang Deng, Yong-Ping Dong, Ji-Zhao Guo
Journal of Electroanalytical Chemistry 2008 Volume 612(Issue 2) pp:277-287
Publication Date(Web):15 January 2008
DOI:10.1016/j.jelechem.2007.09.036
The curves of ECL intensity (IECL) versus potential (E) (IECL–E curves) were obtained when the electrochemiluminescence (ECL) of luminol was induced by cyclic voltammetry (CV). In the IECL–E curves, if there was an ECL peak during initial scan, a corresponding ECL peak called as a counter-peak was usually observed around the similar potential during the reversal scan. In the present work, a couple of strong and well-resolved ECL peaks were found in a model luminol solution consisted of 0.1 mol/L glycine–NaOH buffer system at pH 11.0 and 0.1 mol/L NaNO3 at a gold electrode. The effects of various factors on this couple of ECL peaks, including electrolyte, buffer solution, electrode material, pH, N2/O2/air atmosphere, scan rate, and electrochemical technique, were studied. On this basis, a continuous electron transfer coupled with a competitive chemical reaction (E-E/C) mechanism involved in an accumulation and consumption model has been proposed for the formation of the ECL counter-peak. Electrochemical digital simulation method was used to simulate the formation of the ECL counter-peak according to the proposed E-E/C mechanism. The results also supported the mechanism. Subsequently, it was further validated that ECL peak width, reversal potential and coexisted electroactive species were three important factors affecting the emergence and intensity of the ECL counter-peak. The proposed E-E/C mechanism is considered to be the general explanation of usual counter-peak phenomenon in the luminol ECL under CV conditions since the mechanism is involved in most pathways of the luminol ECL.
Co-reporter:Wei Wang
The Journal of Physical Chemistry C 2008 Volume 112(Issue 29) pp:10759-10766
Publication Date(Web):June 27, 2008
DOI:10.1021/jp802028r
By reducing HAuCl4 with chemiluminescent (CL) reagent luminol in the presence of hydrophilic polymer chitosan, three-dimensional flowerlike gold nanostructures (AuNFs) were synthesized via a convenient one-pot method. As-prepared stable and monodisperse AuNFs were consisted of smaller-sized nanodots according to subsequent characterizations by high-resolution transmission electron microscopy, scanning electron microscopy, and powder X-ray diffraction. The size and morphology of AuNFs could be tailored by varying the amount of luminol or chitosan, which further influenced their surface plasmon resonance (SPR) properties in both visible and near-infrared regions. On the basis of the characterizations, a chitosan-assisted second-growth mechanism was proposed to explain their formations and morphology evolutions with the amount of reactants. Moreover, an electromagnetic simulation method, discrete dipole approximation, was introduced to calculate the morphology-dependent extinction spectra of geometrically irregular AuNFs. The simulations were consistent with the experimental results. Finally, because luminol was attached on the surface of AuNFs, as-prepared AuNFs could react with H2O2 to generate chemiluminescence. The functionalized AuNFs were immobilized on the solid supports by virtue of the film-forming property of chitosan solution to fabricate a reagent-free CL sensor for the determination of H2O2. Due to their shape-dependent SPR properties and specific surface structures, these AuNFs might also have great potential for the applications in biomedicine and surface enhanced Raman scattering.
Co-reporter:Wei Wang, Xuan Yang and Hua Cui
The Journal of Physical Chemistry C 2008 Volume 112(Issue 42) pp:16348-16353
Publication Date(Web):2017-2-22
DOI:10.1021/jp804970x
A facile method is proposed for the room-temperature synthesis of flowerlike gold nanostructures (AuNFs) with a size of 50−115 nm by reducing HAuCl4 with ascorbic acid (AA) in the presence of chitosan. It was found that the concentration of chitosan controlled the size, while that of AA influenced the morphology of as-prepared AuNFs. With higher concentration of AA flowerlike nanostructures were produced, whereas with lower concentration of AA quasi-spherical nanoparticles were formed. Time-dependent surface plasmon resonance (SPR) absorption spectroscopy and the resonance Rayleigh scattering (RRS) technique were used to monitor the growth processes. According to the temporal evolutions of SPR maximum absorption wavelength and RRS intensity, a second growth mechanism is proposed to explain the effect of AA concentration on the morphology and the effect of chitosan concentration on the size of obtained gold nanostructures. In order to determine whether or not the present method is suitable for synthesis of flowerlike gold nanostructures by use of other reductants in the presence of chitosan, four other conventional reductants, including gallic acid (GA), oxalate acid (OA), tartaric acid (TA), and sodium citrate (Cit), instead of AA were examined. The intrinsic reason for the different performances of these reductants was further investigated, and the results also supported the proposed second growth mechanism.
Co-reporter:Ming-Juan Shi, Hua Cui
Journal of Luminescence 2007 Volume 126(Issue 1) pp:187-195
Publication Date(Web):September 2007
DOI:10.1016/j.jlumin.2006.06.010
The electrochemiluminescence (ECL) behavior of fluorescein at a polycrystalline gold electrode was studied under conventional cyclic voltammetric conditions. Five ECL peaks were observed at 0.94 (ECL-1), 1.51 (ECL-2), 1.34 (ECL-3), −0.06 (ECL-4), −0.73 to −1.11 V (ECL-5, a broad weak wave) (vs. SCE), respectively, on the curve of ECL intensity versus potential. These ECL peaks were found to depend on the pH of the solution, supporting electrolyte, potential scan ranges and directions. The emitter of ECL peaks was identified as fluorescein or eosin Y produced on the electrode by analyzing the ECL spectra and fluorescence spectra. The mechanisms for ECL peaks have been proposed due to the reactions of fluorescein and the electro-oxidation product of fluorescein with various oxygen-containing species in the solution or electrogenerated at different applied potentials such as O2, O2·−, HO2−, and BrO−. Singlet molecular oxygen was generated during the reactions and transferred its energy to the ECL emitter such as fluorescein or eosin Y, emitting light.
Co-reporter:Hua Cui;Cheng-Ming Wang
Luminescence 2007 Volume 22(Issue 1) pp:35-45
Publication Date(Web):27 JUL 2006
DOI:10.1002/bio.924
The electrochemiluminescence (ECL) behaviour of luminol on a silver nanoparticle self-assembled gold electrode in neutral and alkaline solutions was investigated using conventional cyclic voltammetry (CV). The silver nanoparticle self-assembled gold electrode exhibited excellent ECL properties for the luminol ECL system. In neutral solutions, four ECL peaks (ECL-1–ECL-4) were observed at 0.73, 1.15, -0.46 and -1.35 V (vs. SCE), respectively. The intensities of these peaks were enhanced significantly compared with those on a bulk gold electrode and a gold nanoparticle self-assembled gold electrode. It was found that ECL-1 and ECL-2 on a silver nanoparticle-modified electrode were about 1000 and 1770 times stronger than those on a bare Au electrode and were about 17 and 15 times stronger than those on a gold nanoparticle-modified electrode, respectively. In alkaline solutions, four ECL peaks were also observed that were much stronger than those in neutral solutions, and ECL-1 and ECL-2 were enhanced by about three orders and one order of magnitude compared with those on a bare Au electrode and on a gold nanoparticle self-assembled electrode, respectively. Moreover, the silver nanoparticle-modified electrode exhibited good stability and reproducibility for luminol ECL. These peaks were found to depend on a number of factors, including silver nanoparticles on the surface of the modified electrode, potential scan direction, scan rate, scan range, the presence of O2 or N2, pH values, the concentrations of NaBr and luminol, and buffer solutions. The emitter of the ECL was confirmed as 3-aminophthalate by analysing the CL spectra. The surface state of the silver nanoparticle self-assembled electrode was characterized by scanning electron microscopy (SEM) and the interface property of the electrode was studied by electrochemical impedance spectroscopy (EIS). A mechanism for the formation of these ECL peaks is proposed. The results demonstrate that luminol has excellent ECL properties, such as strong ECL intensity and good reproducibility on a silver nanoparticle-modified gold electrode, in both neutral and alkaline solutions, which is of great potential in analytical applications. Copyright © 2006 John Wiley & Sons, Ltd.
Co-reporter:Sheng-Liang Xu
Luminescence 2007 Volume 22(Issue 2) pp:77-87
Publication Date(Web):6 NOV 2006
DOI:10.1002/bio.929
Platinum colloids prepared by the reduction of hexachloroplatinic acid with citrate in the presence of different stabilizers were found to enhance the chemiluminescence (CL) of the luminol–H2O2 system, and the most intensive CL signals were obtained with citrate-protected Pt colloids synthesized with citrate as both a reductant and a stabilizer. Light emission was intense and reproducible. Transmission electron microscopy and X-ray photoelectron spectroscopy studies were conducted before and after the CL reaction to investigate the possible CL enhancement mechanism. It is suggested that this CL enhancement is attributed to the catalysis of platinum nanoparticles, which could accelerate the electron-transfer process and facilitate the CL radical generation in aqueous solution. The effects of Pt colloids prepared by the hydroborate reduction were also investigated. The application of the luminol–H2O2–Pt colloids system was exploited for the determination of compounds such as uric acid, ascorbic acid, phenols and amino acids. Copyright © 2006 John Wiley & Sons, Ltd.
Co-reporter:Hua Cui ;Wei Wang Dr.;Chun-Feng Duan;Yong-Ping Dong;Ji-Zhao Guo
Chemistry - A European Journal 2007 Volume 13(Issue 24) pp:
Publication Date(Web):31 MAY 2007
DOI:10.1002/chem.200700011
It was found that chloroauric acid (HAuCl4) could be directly reduced by the luminescent reagent luminol in aqueous solution to form gold nanoparticles (AuNPs), the size of which depended on the amount of luminol. The morphology and surface state of as-prepared AuNPs were characterized by transmission electron microscopy, UV/visible spectroscopy, X-ray photoelectron spectroscopy, FTIR spectroscopy, and thermogravimetric analysis. All results indicated that residual luminol and its oxidation product 3-aminophthalate coexisted on the surface of AuNPs through the weak covalent interaction between gold and nitrogen atoms in their amino groups. Subsequently, a luminol-capped AuNP-modified electrode was fabricated by the immobilization of AuNPs on a gold electrode by virtue of cysteine molecules and then immersion in a luminol solution. The modified electrode was characterized by cyclic voltammetry, electrochemical impedance spectroscopy, and scanning electron microscopy. The as-prepared modified electrode exhibited an electrochemiluminescence (ECL) response in alkaline aqueous solution under a double-step potential. H2O2 was found to enhance the ECL. On this basis, an ECL sensor for the detection of H2O2 was developed. The method is simple, fast, and reagent free. It is applicable to the determination of H2O2 in the range of 3×10−7–1×10−3 mol L−1 with a detection limit of 1×10−7 mol L−1 (S/N=3).
Co-reporter:Zhi-Feng Zhang, Hua Cui and Ming-Juan Shi
Physical Chemistry Chemical Physics 2006 vol. 8(Issue 8) pp:1017-1021
Publication Date(Web):08 Dec 2005
DOI:10.1039/B511917K
It was found that potassium permanganate (KMnO4) could react with gold nanoparticles in a strong acid medium to generate particle size-dependent chemiluminescence (CL). For gold nanoparticles with the size of 2.6 or 6.0 nm, the reaction was fast and could produce the excited state Mn(II)* with light emission around 640 nm. For gold nanoparticles larger than 6.0 nm, no light emission was observed due to a much slower reaction rate. The CL intensity was found to increase linearly with the concentration of 2.6 nm gold nanoparticles. The effects of the acid medium, concentration of KMnO4 and presence of N2 and O2 were investigated. UV-Vis absorption spectra and X-ray photoelectron spectra (XPS) measured before and after the CL reaction were analyzed. A CL mechanism has been proposed suggesting that the potassium permanganate was reduced by gold nanoparticles in the strong acid medium to the excited state Mn(II)*, yielding light emission. The results bestow new light on the size-dependent chemical reactivities of the gold nanoparticles and on nanoparticle-induced chemiluminescence. The CL reaction was considered to be of potential use for bioanalysis applications.
Co-reporter:Guo-Hui Wan, Hua Cui, Yi-Lan Pan, Ping Zheng, Li-Juan Liu
Journal of Chromatography B 2006 Volume 843(Issue 1) pp:1-9
Publication Date(Web):20 October 2006
DOI:10.1016/j.jchromb.2006.05.017
A novel method was developed for the determination of quinolone (QN) residues such as ofloxacin, norfloxacin, ciprofloxacin and lomefloxacin by high-performance liquid chromatography (HPLC) coupled with chemiluminescence (CL) detection. The procedure was based on the chemiluminescent enhancement by QNs of the Ce(SO4)2–Ru(bpy)32+–HNO3 system. The separation was carried out with an isocratic elution using the mobile phase of 3:15:82 (v/v/v) acetonitrile–methanol–ammonium acetate buffer (containing 7.5 × 10−4 M TBAB, 0.8% (v/v) TEA and 1.0 × 10−4 M ammonium acetate, pH 3.65) at a flow rate of 1.0 ml/min. For the four QNs, the detection limits at a signal-to-noise of 3 ranged from 0.36 to 2.4 ng/ml. The relative standard deviations for the determination of QNs ranged from 1.6 to 4.5% within a day (n = 11) and from 3.7 to 6.2% in three days (n = 15), respectively. The method was successfully applied to the determination of QNs in prawn samples. The possible mechanism of the CL reaction was also discussed briefly.
Co-reporter:Hai-Song Zheng;Guo-Hui Wan;Xiao-Feng Yu;Li-Juan Liu;Yong-Qiang Pang
Luminescence 2006 Volume 21(Issue 1) pp:36-42
Publication Date(Web):15 AUG 2005
DOI:10.1002/bio.880
A novel flow-injection method with chemiluminescence detection was developed for the determination of streptomycin residues in milk, based on the enhancement by streptomycin of the luminol–potassium periodate–Mn2+ chemiluminescence system. The assay allowed analysis of streptomycin residues in whole milk samples (∼3.5% fat) after sample work-up procedures. The limit of detection was 5.16 × 10−9 mol/L for milk, and was far below the regulations of maximum residue limits (MRLs). The relative standard deviation (RSD) for 8.66 × 10−8 mol/L streptomycin was 1.94% (n = 15) in milk. The results obtained for the assay of streptomycin residues in milk was comparable with those obtained by the official methods (ELISA) and demonstrated good accuracy and precision. The possible mechanism is briefly discussed. Copyright © 2005 John Wiley & Sons, Ltd.
Co-reporter:Hong-Xiao Yu;Jun-Bo Guan
Luminescence 2006 Volume 21(Issue 2) pp:81-89
Publication Date(Web):17 JAN 2006
DOI:10.1002/bio.888
Cathodic electrochemiluminescence (ECL) behaviours of the acetonitrile, acetonitrile–1,10-phenanthroline (phen) and acetonitrile–ternary Eu(III) complex systems at a gold electrode were studied. One very weak cathodic ECL-2 at −3.5 V was observed in 0.1 mol/L tetrabutylammonium tetrafluoroborate (TBABF4) acetonitrile solution. When 10 mmol/L tetrabutylammonium peroxydisulphate [(TBA)2S2O8] was added to 0.1 mol/L TBABF4 acetonitrile solution, another cathodic ECL-1 at −2.7 V appeared and the potential for ECL-2 was shifted from −3.5 to −3.1 V. Furthermore, ECL-2 intensity was enhanced about 20-fold. When 1 × 10−4 mol/L phen was added to 0.1 mol/L TBABF4 + 10 mmol/L (TBA)2S2O8 acetonitrile solution, the ECL intensities of ECL-1 and ECL-2 were enhanced about 20-fold compared with those of 0.1 mol/L TBABF4 + 10 mmol/L (TBA)2S2O8 acetonitrile solution. The maximum emission peaks of ECL-1 and ECL-2 in the three systems mentioned above appeared at about 530 nm. The products obtained by electrolysing 0.1 mol/L TBABF4 acetonitrile solution at −3.5 V for 20 min were analysed by Fourier Transform Infrared (FTIR) spectra and gas chromatography–mass spectrometry (GC–MS) and the emitter of ECL-1 and ECL-2 was identified as excited state polyacetonitrile. When ternary Eu(III) complexes were presented in 0.1 mol/L TBABF4 + 10 mmol/L (TBA)2S2O8 acetonitrile solution, another maximum emission peak with a narrow band centred at about 610 nm appeared in ECL-1 in addition to the maximum emission peaks at about 530 nm for ECL-1 and ECL-2. The emitter of ECL emission at 610 nm was identified as the excited states Eu(III)*. The mechanisms for cathodic ECL behaviours of the acetonitrile, acetonitrile–phen and acetonitrile–ternary Eu(III) complex systems at a gold electrode have been proposed. The extremely sharp emission bands for ternary Eu(III) complexes may have analytical potential. Copyright © 2006 John Wiley & Sons, Ltd.
Co-reporter:Chun-Feng Duan;Chun-Ze Lai;Li-Juan Liu;Zhi-Feng Zhang;Hong Xu;Mei Lian
Luminescence 2006 Volume 21(Issue 3) pp:195-201
Publication Date(Web):27 APR 2006
DOI:10.1002/bio.905
The effects of 36 organic compounds on luminol–KIO4–H2O2 chemiluminescence (CL) were studied. It was found that most of the tested compounds could inhibit or enhance the CL intensity. The activities of such inhibitors or enhancers were related to the pH of the CL system and the number and position of functional groups such as –OH and –NH2 on aromatic rings. The mechanism of the CL inhibition and enhancement was considered. Based on the CL inhibition or enhancement, the possibility of analytical applications was explored. The results demonstrated that numerous compounds were detectable at the ng/mL level using the CL system. Copyright © 2006 John Wiley & Sons, Ltd.
Co-reporter:Hua Cui, Qunlin Zhang, Aung Myint, Xuewu Ge, Lijuan Liu
Journal of Photochemistry and Photobiology A: Chemistry 2006 Volume 181(2–3) pp:238-245
Publication Date(Web):31 July 2006
DOI:10.1016/j.jphotochem.2005.12.003
The oxidation reaction between cerium(IV) and rhodamine 6G in sulfuric acid medium underwent weak chemiluminescence (CL). The effects of 53 organic compounds of interest on cerium(IV)–rhodamine 6G chemiluminescence were investigated by a flow injection procedure, and 32 phenolic compounds were found to enhance CL. Phenolic compounds mainly include phenols, polyphenols, phenolic acids, hydroxycinnamic acids and flavonoids. The correlation between CL and molecular structure was systematically studied. It was noteworthy that phenolic hydroxyls were the main active groups for the generation of CL. The magnitude of CL was related to the type and position of substituents in the benzene ring. The maximal emission wavelength of CL spectra for all tested phenolic compounds was at about 555 nm, and luminophors were assigned to rhodamine 6G. Based on the studies of kinetic process and the spectra of CL, fluorescence and UV–vis absorption, a CL mechanism has been proposed to be due to that rhodamine 6G and phenolic compound are oxidized by cerium(IV) to form the excited-state cerium(III), which transfers energy to rhodamine 6G, resulting in light emission. However, on the other hand, if the oxidation products of some phenolic compounds such as benzoquinone or ketone could significantly quench the emissive rhodamine 6G via energy transfer, no light emission was observed for such compounds as hydroquinone and catechol.
Co-reporter:Qunlin Zhang
Journal of Separation Science 2005 Volume 28(Issue 11) pp:1171-1178
Publication Date(Web):14 JUL 2005
DOI:10.1002/jssc.200500055
A novel method based on reversed-phase high-performance liquid chromatography with chemiluminescence detection has been developed for the simultaneous determination of three flavonols including quercetin, kaempferol, and isorhamnetin. The procedure was based on the chemiluminescent enhancement by flavonols of the cerium(IV)-rhodamine 6G system in sulfuric acid medium. The effects of several parameters on the HPLC resolution and CL emission were studied systematically. Good separation was achieved with isocratic elution using a mixture of methanol and aqueous 1.0% acetic acid (37 : 63, v/v) within 25 min. Under optimized conditions, the linear working range covers 3 orders of magnitude with relative standard deviations below 4.5% for 11 replicate injected flavonol samples, and detection limits (S/N = 3) were 1.6×10–8, 3.5×10–9, and 6.5×10–9 g mL–1 for quercetin, kaempferol, and isorhamnetin, respectively. The chemiluminescence reaction was compatible with the mobile phase of high-performance liquid chromatography. The proposed method has been successfully applied to the determination of three active flavonols in phytopharmaceuticals of Hippophae rhamnoides L. After a simple extraction procedure, the repeatability and recovery were satisfactory.
Co-reporter:Qunlin Zhang;Aung Myint;Xuewu Ge;Lijuan Liu;Guixin Chou
Phytochemical Analysis 2005 Volume 16(Issue 6) pp:440-445
Publication Date(Web):15 SEP 2005
DOI:10.1002/pca.867
A sensitive and selective flow injection chemiluminescence method for the determination of cardamonin over the range 1.0 × 10−8 to 8.0 × 10−6 g/mL is described. The method is based on the enhancement by cardamonin of the chemiluminescence of the reaction between cerium (IV) and rhodamine 6G in sulphuric acid medium. The optimised flow injection procedure yielded a detection limit for cardamonin of 8.8 × 10−9 g/mL, whilst the relative standard deviations of intraday and inter-day precision were below 2.5%. The method has the advantages of high sensitivity and a wide linear range. It was successfully applied to the determination of cardamonin in Alpinia katsumadai Hayata. The mechanism of the chemiluminescence reaction is proposed. Copyright © 2005 John Wiley & Sons, Ltd.
Co-reporter:Guo-Hui Wan, Hua Cui, Hai-Song Zheng, Jian Zhou, Li-Juan Liu, Xiao-Feng Yu
Journal of Chromatography B 2005 Volume 824(1–2) pp:57-64
Publication Date(Web):25 September 2005
DOI:10.1016/j.jchromb.2005.06.039
A novel method was developed for the simultaneous determination of tetracycline antibiotic (TCA) residues such as oxytetracycline (OTC), tetracycline (TC), and metacycline (MTC) by high-performance liquid chromatography (HPLC) coupled with chemiluminescence (CL) detection. The procedure was based on the chemiluminescent enhancement by TCAs of the potassium permanganate–sodium sulfite–β-cyclodextrin system in a phosphoric acid medium. The separation was carried out with an isocratic elution using a mixture of acetonitrile and 0.001 M phosphoric acid. For the three TCAs, the detection limits at a signal-to-noise of 3 ranged from 0.9 to 5.0 ng/ml. The relative standard deviations for the determination of TCAs ranged from 3.1 to 7.4% within a day (n = 11) and ranged from 2.2 to 8.6% in 3 days (n = 9), respectively. The method was successfully applied to the determination of TCA residues in honey samples. The possible mechanism of the CL reaction was also discussed.
Co-reporter:Hua Cui;Hai-Song Zheng;Guo-Hui Wan;Li-Juan Liu;Xiao-Feng Yu;Yong-Qiang Pang
Luminescence 2005 Volume 20(Issue 1) pp:8-15
Publication Date(Web):31 JAN 2005
DOI:10.1002/bio.793
Tetracyclines (TCs) were found to strongly inhibit the electrochemiluminescence (ECL) from the Ru(bpy)32+–tripropylamine system when a working Pt electrode was maintained at 1.05 V (vs. Ag[sol ]AgCl) in pH 8.0 carbonate buffer solution. On this basis, a flow injection (FI) procedure with inhibited electrochemiluminescence detection has been developed for the determination of tetracycline (TC) and oxytetracycline (OTC). Under the optimized condition, the linear ranges of 2.0 × 10−8–1.0 × 10−5 and 1.0 × 10−8–1.0 × 10−5 g[sol ]mL and the detection limits of 4.0 × 10−9 and 3.8 × 10−9 g[sol ]mL were obtained for TC and OTC, respectively. The relative standard deviations (RSD) were 0.68% and 1.18% for 5.0 × 10−7 g[sol ]mL TC and OTC (n = 13), respectively. The method showed higher sensitivity than most of the reported methods. It was successfully applied to the determination of tetracycline in a Chinese proprietary medicine, Tetracyclini and Cortisone Eye Ointment, and the residues of tetracycline in honey products. The inhibition mechanism has been proposed due to an energy transfer between electrogenerated Ru(bpy)32+* and benzoquinone derivatives at the electrode surface. Copyright © 2005 John Wiley & Sons, Ltd.
Co-reporter:Jian Zhou, Hua Cui, Guohui Wan, Hong Xu, Yongqiang Pang, Chunfeng Duan
Food Chemistry 2004 Volume 88(Issue 4) pp:613-620
Publication Date(Web):December 2004
DOI:10.1016/j.foodchem.2004.05.003
A novel high-performance liquid chromatography with chemiluminescence detection has been developed for the determination of trans-resveratrol in red wines based on the enhancement by trans-resveratrol of the chemiluminescence from luminol–potassium ferricyanide system in alkaline medium. Samples were separated on a C8 column using isocratic elution of methanol/water (35:65). Quantification of trans-resveratrol in Chinese red wines was performed without any sample pretreatment. It allows for the determination of trans-resveratrol in the range 0.5–750 μg/L with a detection limit of 0.166 μg/L (S/N=3). The relative standard deviation (RSD) is 1.16% for 7.5 μg/L trans-resveratrol (n=11). trans-Resveratrol was detected in Chinese red wines with the recoveries of 92.2–114.7%. Concentrations ranged from 0.072 to 1.607 mg/L in Chinese red wines.
Co-reporter:Qunlin Zhang, Aung Myint, Lijuan Liu, Xuewu Ge, Hua Cui
Journal of Pharmaceutical and Biomedical Analysis 2004 Volume 36(Issue 3) pp:587-592
Publication Date(Web):15 November 2004
DOI:10.1016/j.jpba.2004.07.036
Strong chemiluminescence was observed when cerium(IV) reacted with rhodamine 6G in sulfuric acid medium in the presence of puerarin. This phenomenon has been utilized to design a sensitive and selective flow injection-chemiluminescence method for the determination of puerarin. Under the optimum conditions, the proposed procedure has a linear range between 1.3 × 10−9 and 8.0 × 10−7 g/mL, with a detection limit of 8.4 × 10−10 g/mL puerarin and a relative standard deviation of 1.86% (n = 11) at 5.0 × 10−8 g/mL puerarin. The method was successfully applied to the determination of puerarin in pharmaceutical preparations. The mechanism of this chemiluminescence reaction has been proposed.
Co-reporter:Hong-Xiao Yu;Ji-Zhao Guo
Luminescence 2004 Volume 19(Issue 4) pp:212-221
Publication Date(Web):27 JUL 2004
DOI:10.1002/bio.778
Multi-channel electrochemiluminescence (ECL) of luminol at a copper electrode has been studied under conventional cyclic voltammetric (CV) conditions. Compared with the ECL of luminol at other electrodes, three ECL peaks were observed at 0.30, −0.24 and −0.65 V (vs. SCE), respectively, which was also imaged by a CCD camera. The effects of potential scan direction, anodic reverse potential, the presence of N2 and O2 of the solution, the pH of the solution, the NaNO3 concentration and the potential scan rate were examined. The effect of n-alkanethiol self-assembled monolayers on copper electrodes and 20 l-amino acids, dopamine, adrenaline and noradrenaline on the ECL of luminol were also investigated. The emission spectra of various ECL peaks at different potentials demonstrated that all ECL peaks were related to the luminol reaction. The results show that the oxygen dissolved in solution and copper oxide covered on the surface of the electrode play an important role in the luminol ECL process at a copper electrode. It has been proposed that three ECL channels of luminol at a copper electrode resulted from the reactions of luminol or luminol radical electrooxidized by luminol with various electrogenerated oxygen-containing species, such as O2, OOH− and copper oxides at different potentials. Copyright © 2004 John Wiley & Sons, Ltd.
Co-reporter:Jian Zhou, Hong Xu, Guo-Hui Wan, Chun-Feng Duan, Hua Cui
Talanta 2004 Volume 64(Issue 2) pp:467-477
Publication Date(Web):8 October 2004
DOI:10.1016/j.talanta.2004.03.015
The effect of 36 aromatic compounds on the luminol–dimethylsulfoxide–OH− chemiluminescence (CL) was systematically studied. It was found that dihydroxybenzenes, and ortho- and para-substituted aminophenols and phenylenediamines inhibited the CL and phenols with three or more than three hydroxyls except phloroglucin tended to enhance the CL. The CL inhibition and enhancement was proposed to be dependent on whether superoxide anion radical (O2−) was competitively consumed by compounds in the CL system. Trihydroxybenzenes were capable of generating superoxide anion radical, leading to the CL enhancement, whereas dihydroxybenzenes were superoxide anion radical scavenger, causing the CL inhibition. Based on the inhibited CL, a novel method for the simultaneous determination of p-phenylenediamine, o-phenylenediamine, p-aminophenol, o-aminophenol, resorcinol and hydroquinone by high-performance liquid chromatography coupled with chemiluminescence detection was developed. The method has been successfully applied to determine intermediates in oxidative hair dyes and wastewater of shampooing after hair dyed.
Co-reporter:Hua Cui;Xiang-Qin Lin;Xiao-Yu Zhao
Luminescence 2003 Volume 18(Issue 4) pp:199-202
Publication Date(Web):12 AUG 2003
DOI:10.1002/bio.724
Two cathodic electrochemiluminescence (ECL) peaks have been obtained at −0.99 and −1.80 V (vs. SCE), respectively, from Ru(bpy)/Nafion coated onto a graphite oxide electrode in purely aqueous solution under cyclic voltammetric (CV) conditions, without addition of any reducing or oxidative reagents. These two ECL peaks were found to correlate to initial scan direction, pH, and reversal potential. Nafion played an important role in the generation of these two ECL peaks because no cathodic emission was observed in the system without Nafion. It seems that a part of Ru(bpy) electrogenerated at positive potential can remain in the Nafion, even at negative potentials. It was confirmed that Ru(bpy)+ was formed at −1.80 V by addition of S2O. The ECL peak at −0.99 V is attributed to the reaction of Ru(bpy)3+ and OH−. The ECL peak at −1.80 V is probably due to the annihilation reaction of Ru(bpy)3+ and Ru(bpy)+. Copyright © 2003 John Wiley & Sons, Ltd.
Co-reporter:Hua Cui;Cheng-gen Xie;Chun-ze Lai
Luminescence 2003 Volume 18(Issue 6) pp:318-323
Publication Date(Web):11 DEC 2003
DOI:10.1002/bio.740
It was found that the inhibition and enhancement by phloroglucinol of the chemiluminescence from the luminol–K3Fe(CN)6 system were dependent on the pH of luminol solution and the concentration of phloroglucinol. In Na2CO3–NaHCO3 buffer, phloroglucinol exhibited strong chemiluminescent enhancement at pH 9.4. On this basis, a flow injection method was developed for the determination of phloroglucinol. The method was simple, rapid, convenient and sensitive, with a detection limit of 2.0 × 10−9 mol/L. It is effective for determining phloroglucinol in the range of 1.0 × 10−5–5.0 × 10−9 mol/L. The relative standard deviation is 1.3% within one day and 3.2% between days for the determination of 5.0 × 10−7 mol/L phloroglucinol. The method has been successfully used to determine phloroglucinol in environmental water, with satisfactory results. Copyright © 2003 John Wiley & Sons, Ltd.
Co-reporter:Feng Li, Yong-Qiang Pang, Xiang-Qin Lin, Hua Cui
Talanta 2003 Volume 59(Issue 3) pp:627-636
Publication Date(Web):1 March 2003
DOI:10.1016/S0039-9140(02)00576-3
Two maximal potential-resolved flow injection-electrochemiluminescent (FI-ECL) peaks were observed for Ru(bpy)32+/TPrA system at 0.90 and 1.05 V, and for Ru(phen)32+/TPrA at 1.01 and 1.25 V (vs. Ag/AgCl) in pH 8.0 phosphate buffer solutions. Sensitive ECL inhibition effects were observed in the presence of noradrenaline and dopamine for both of these systems. Therefore, an FI-ECL inhibition method for determination of noradrenaline and dopamine has been developed. Under optimal conditions, linear responses between logarithm of ECL intensity changes and logarithm of sample concentration were found for noradrenaline in the linear range (LR) of 4×10−8–1×10−5 mol l−1 with theoretical detection limit (DL) of 2.5×10−8 mol l−1 for Ru(bpy)32+/TPrA system, and in LR of 2×10−8–2×10−5 mol l−1 with DL of 7.1×10−9 mol l−1 for Ru(phen)32+/TPrA system; and for dopamine in LR of 8×10−8–2×10−5 mol l−1 with DL of 5.2×10−8 mol l−1 for Ru(bpy)32+/TPrA system, in LR of 4×10−8–2×10−5 mol l−1 with DL of 1.5×10−8 mol l−1 for Ru(phen)32+/TPrA system. It was applied for determination of commercial pharmaceutical injection samples with satisfied results. The mechanism of the inhibition effects was proposed in the preliminary way.
Co-reporter:Feng Li, Hua Cui, Xiang-Qin Lin
Analytica Chimica Acta 2002 Volume 471(Issue 2) pp:187-194
Publication Date(Web):7 November 2002
DOI:10.1016/S0003-2670(02)00930-3
Adrenaline was found to inhibit strongly the electrochemiluminescence (ECL) from the Ru(bpy)32+/tripropylamine system when a working Pt electrode was maintained at 1.05 V (versus Ag/AgCl) in pH 8.0 phosphate buffer. On this basis, a flow injection (FI) procedure with inhibited electrochemiluminescence detection has been developed for determination of adrenaline. The method exhibited a good reproducibility, sensitivity, and stability with a detection limit (signal-to-noise ratio = 3) of 7.0×10−9 mol l−1 and dynamic concentration range of 2×10−8 to 1×10−4 mol l−1. The relative standard deviation was 2.2% for 1.0×10−6 mol l−1 adrenaline (n=11). The method was successfully applied to the determination of adrenaline in pharmaceutical samples. Moreover, ECL emission spectra, UV-Vis absorption spectra and cyclic voltammograms of Ru(bpy)32+/tripropylamine/adrenaline were studied. The inhibition mechanism has been proposed as the interaction of electrogenerated Ru(bpy)32+* and the o-benzoquinone derivatives, adrenochrome and adrenalinequinone, at the electrode surface.
Co-reporter:Feng Li;Xiang-Qin Lin
Luminescence 2002 Volume 17(Issue 2) pp:117-122
Publication Date(Web):7 FEB 2002
DOI:10.1002/bio.674
The electrogenerated chemiluminescence of Ru(bpy)32+/C2O42− system on a pre-polarized Au electrode was studied using a potential-resolved electrochemiluminescence (PRECL) method. Two anodic ECL peaks were observed at 1.22 V (vs. SCE) (EP1), 1.41 V (vs. SCE) (EP2), respectively. The effects of the concentration of oxalate and Ru(bpy)32+, adsorbed sulphur, CO2, O2, pH of the solution and pretreatment of the Au electrode on the two PRECL peaks were examined. The surface state of the pre-oxidized gold electrode was also studied using the X-ray photoelectron spectroscopy (XPS) technique. Moreover, comparative studies on i–E and I–E curves were carried out and a possible mechanism involving both the catalytic and the direct electro-oxidation pathways was proposed for the ECL of Ru(bpy)32+/C2O42− system. EP1 is attributed to the Ru(bpy)32/3+ reaction catalysed by C2O42− to generate Ru(bpy)32+*. EP2 is likely because C2O42− was oxidized at the electrode to form CO2−·, followed by reaction with Ru(bpy)33+ to generate Ru(bpy)32+*. Copyright © 2002 John Wiley & Sons, Ltd.
Co-reporter:Hua Cui, Shifeng Li and Xiangqin Lin
Analyst 2001 vol. 126(Issue 5) pp:553-554
Publication Date(Web):11 Apr 2001
DOI:10.1039/B102215F
It was found that cerium(IV) reacted with surfactant Tween 20 in acidic medium to generate green chemiluminescence. The maximum emission wavelength was about 478 nm. The enhancement and inhibition of the CL reaction by some polyphenols and anilines was studied and the possibility of analytical application was explored.
Co-reporter:Yi He, Danqing Liu, Xinyuan He and Hua Cui
Chemical Communications 2011 - vol. 47(Issue 38) pp:NaN10694-10694
Publication Date(Web):2011/09/05
DOI:10.1039/C1CC14389A
A novel one-pot method for the synthesis of chemiluminescence functionalized AgNPs has been reported and an ECL sensor has been developed for the detection ofM. tuberculosisDNA.
Co-reporter:Chun-Feng Duan and Hua Cui
Chemical Communications 2009(Issue 18) pp:NaN2576-2576
Publication Date(Web):2009/03/26
DOI:10.1039/B901232J
Ethanol can initiate Pt nanoparticles to catalyze the chemiluminescent reaction of alkaline lucigenin solution, leading to a visible light emission with autocatalytic property.
Co-reporter:Danqing Liu, Guangming Huang, Yuqi Yu, Yi He, Hongli Zhang and Hua Cui
Chemical Communications 2013 - vol. 49(Issue 84) pp:NaN9796-9796
Publication Date(Web):2013/08/23
DOI:10.1039/C3CC44765K
Herein, we report a facile strategy for the synthesis of dual-functionalized graphene hybrids (A–H–GNs) based on interactions among graphene, N-(aminobutyl)-N-(ethylisoluminol) (ABEI) and hemin. The multilayers of a chemiluminescence reagent (ABEI) and a catalyst (hemin) were accumulated on the graphene surface, resulting in high chemiluminescence performance, good solubility and stability in aqueous solution.
Co-reporter:Yi He, Yuting Chen, Chongying Li and Hua Cui
Chemical Communications 2014 - vol. 50(Issue 59) pp:NaN7997-7997
Publication Date(Web):2014/05/01
DOI:10.1039/C4CC01242A
A general strategy was developed to fabricate 2-to-1, 4-to-2 and 8-to-3 molecular encoders and a 1-to-2 decoder by assembling graphene oxide with various dye-labeled DNAs.
Co-reporter:Wen Shen, Yuqi Yu, Jiangnan Shu and Hua Cui
Chemical Communications 2012 - vol. 48(Issue 23) pp:NaN2896-2896
Publication Date(Web):2012/01/23
DOI:10.1039/C2CC17674B
A bottom-up approach for preparing multifunctional graphene-based materials noncovalently functionalized with CL reagents with aromatic rings such as N-(aminobutyl)-N-(ethylisoluminol) (ABEI), luminol and isoluminol is reported. The as-prepared nanocomposites exhibit good CL activity, which may find future applications in analytical, electrochemical and biomedical fields.
Co-reporter:Jie Jiang, Yi He, Shiyuan Li and Hua Cui
Chemical Communications 2012 - vol. 48(Issue 77) pp:NaN9636-9636
Publication Date(Web):2012/08/09
DOI:10.1039/C2CC34612E
In this communication, we report a general strategy for the production of carbon nanodots (CDs) by microwave irradiation of amino acids in the presence of acid or alkali. The resultant CDs exhibit strong photoluminescence and intense chemiluminescence enhancement of the NaIO4–H2O2 system.
Co-reporter:Dayong Tian, Hongli Zhang, Ying Chai and Hua Cui
Chemical Communications 2011 - vol. 47(Issue 17) pp:NaN4961-4961
Publication Date(Web):2011/03/22
DOI:10.1039/C1CC10435G
A novel strategy for the synthesis of CF-AuNMs by reducing HAuCl4 with ABEI in aqueous solution at room temperature is reported. No additional stabilizing and reducing reagents are needed, and various morphologies of CF-AuNMs can be obtained. It could be used as bio-probe for bioassays.
Co-reporter:Ying Chai, Dayong Tian, Wei Wang and Hua Cui
Chemical Communications 2010 - vol. 46(Issue 40) pp:NaN7562-7562
Publication Date(Web):2010/09/17
DOI:10.1039/C0CC02356F
Luminol functionalized gold nanoparticles were used as labels for electrochemiluminescence signal amplification and an ultrasensitive, highly selective, convenient, low cost DNA detection strategy was developed.
Co-reporter:Hongli Zhang, Mengxiao Liu, Guangming Huang, Yuqi Yu, Wen Shen and Hua Cui
Journal of Materials Chemistry A 2013 - vol. 1(Issue 7) pp:NaN977-977
Publication Date(Web):2012/11/23
DOI:10.1039/C2TB00375A
Herein we report a novel facile synthesis of Au nanopopcorns (AuNPCs) with high chemiluminescent yield by reducing (±)-α-lipoic acid (LA) and HAuCl4 with N-(aminobutyl)-N-(ethylisoluminol) (ABEI) in ethyl alcohol solution at room temperature through a seed growth method. The morphologies of AuNPCs could be changed by adjusting the mole ratios of ABEI, LA and HAuCl4. The characterization results demonstrated that ABEI and the reduction product of LA as stabilizers were coated on the surface of AuNPCs during the synthesis. The AuNPCs, functionalized with ABEI, could react with various oxidants (H2O2, KMnO4, NaClO, Fe(CN)63− and AgNO3) to produce chemiluminescence (CL). The special morphology of AuNPCs maintains the large specific surface area, inherited from its shape and demonstrated excellent catalytic property when involved in CL reaction with H2O2. Thus the CL efficiency of AuNPCs was more than two orders of magnitude higher than that of ABEI functionalized gold nanoparticles in our previous work. The AuNPCs are capable of direct conjugation with protein and DNA while maintaining their luminescent properties, thus they could be potentially useful as a bio-probe for immunoassays and DNA assays.
Co-reporter:Yuqi Yu, Ming Zhou and Hua Cui
Journal of Materials Chemistry A 2011 - vol. 21(Issue 34) pp:NaN12625-12625
Publication Date(Web):2011/07/25
DOI:10.1039/C1JM11843A
Bis(2,2′-bipyridine)(5-amino-1,10-phenanthroline) ruthenium(II) functionalized gold nanoparticles with electrochemiluminescence activity were successfully synthesized by a simple one-pot method via the reduction of HAuCl4 with NaBH4 in the presence of bis(2,2′-bipyridine)(5-amino-1,10-phenanthroline) ruthenium(II), which is of great potential for application in bioanalysis.
Co-reporter:Yi He and Hua Cui
Journal of Materials Chemistry A 2012 - vol. 22(Issue 18) pp:NaN9091-9091
Publication Date(Web):2012/03/26
DOI:10.1039/C2JM16028E
A fast, linker free, one step strategy for in situ preparation of graphene oxide/Ag nanoparticle (GO-AgNP) nano-composites was proposed by reducing AgNO3 with chemiluminescent reagent luminol in the presence of GO. The nano-composites were characterized by transmission electron microscopy, energy-dispersive spectroscopy, X-ray diffraction, UV-Vis absorption spectra, X-ray photoelectron spectroscopy, thermogravimetric analysis, and electrochemical impedance spectroscopy. The results demonstrated that many Ag nanoparticles (AgNPs) with an average diameter of about 22 nm were uniformly dispersed on the surface of GO nanosheets. Luminol molecules were also decorated on the surface of the nano-composites. Thus the nano-composites showed excellent chemiluminescence (CL) activity when reacting with H2O2. Furthermore, the formation mechanism of the as-prepared GO-AgNP nano-composites is proposed as follows: Ag+ adsorbs on the surface of GO via an electrostatic force and Ag+-π orbital interaction. Afterwards, they are in situ gradually reduced by luminol molecules to AgNPs on the surface of GO and some luminol molecules are attached on the surface of the nano-composites. Finally, it was found that glutathione could enhance the CL intensity between GO-AgNP nano-composites and hydrogen peroxide. On this basis, a sensitive and selective method for the detection of glutathione was developed. This method showed a detection limit of 25 μmol L−1 and a linear range from 30 to 1000 μmol L−1. The nano-composites may be attractive and advanced composite materials with great promise as advanced building blocks, CL labels, and platforms for various analytical devices with CL detection such as sensors, microchips and bioassays.
Co-reporter:Qi Li, Fang Li, Wen Shen, Xiangyang Liu and Hua Cui
Journal of Materials Chemistry A 2016 - vol. 4(Issue 16) pp:NaN3484-3484
Publication Date(Web):2016/03/21
DOI:10.1039/C6TC00072J
In this manuscript, lucigenin (Luc) and Co2+ complex bifunctionalized graphene oxide hybrids (Co(Trp)2/Luc/GO) were synthesized via a facile and simple strategy by virtue of π–π stacking and electrostatic interaction. The as-prepared Co(Trp)2/Luc/GO hybrids exhibited good stability, water-solubility and excellent CL activity when reacted with H2O2, which was more than 30 times higher than Luc/GO. The CL mechanism between Co(Trp)2/Luc/GO and H2O2 has been proposed to be due to the fact that Co2+ could facilitate the formation of HO˙, O2˙− and Co2+–HO2−, accelerating lucigenin CL reaction. Moreover, it was also found that ascorbic acid could directly react with Co(Trp)2/Luc/GO to generate CL emission in the presence of dissolved oxygen. By virtue of Co(Trp)2/Luc/GO as a platform, a sensitive, selective, reagent-less and disposable CL sensor for the detection of ascorbic acid was developed. Ascorbic acid could be determined in the range of 5.0 × 10−7–1.0 × 10−3 M with a detection limit of 0.4 μM. This work reveals that catalyst Co(Trp)2 assembled on the surface of Luc/GO exhibits a unique catalytic effect on lucigenin CL reaction, which provides a new strategy for the synthesis of a lucigenin functionalized nanomaterial with high CL efficiency. The synthesized Co(Trp)2/Luc/GO may find more applications in the development of novel analytical methods.
Co-reporter:Na Li, Wei Wang, Dayong Tian and Hua Cui
Chemical Communications 2010 - vol. 46(Issue 9) pp:NaN1522-1522
Publication Date(Web):2010/01/15
DOI:10.1039/B920736H
Luminol could react with acidic Pd–Ag colloid to yield a novel chemiluminescence, which could be reversibly controlled by the pH of Pd–Ag colloid. This offers a novel way to design smart nanomaterials with pH-controlled catalysis.
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