Co-reporter:Shan Sun, Kai Jiang, Sihua Qian, Yuhui Wang, and Hengwei Lin
Analytical Chemistry May 16, 2017 Volume 89(Issue 10) pp:5542-5542
Publication Date(Web):April 28, 2017
DOI:10.1021/acs.analchem.7b00602
Fluorescent carbon dots (CDs) are attracting much attention in sensing recently thanks to their superior optical properties and abundant surface functional groups. To take further advantages of these unique features, CDs are considered to be possible for facilely fabricating multichannel sensor arrays. As a proof-of-concept research, CDs-metal ions ensembles are screened and designed as a triple-channel fluorescent sensor array in this study for the identification of various phosphate anions (e.g., ATP, ADP, AMP, PPi, and Pi) for the first time. Further studies reveal that the selected three metal ions (i.e., Ce3+, Fe3+, and Cu2+) could induce aggregation of the CDs, resulting in quenching of their fluorescence. However, disaggregation or further aggregation of the CDs-metal ions ensembles occurs with the addition of phosphate anions. Consequently, fluorescence of the CDs is recovering or further quenching. On account of various numbers of phosphate group and steric hindrance effects of phosphate anions, their affinities to the sensor array can be distinguished through fluorescence changes of the CDs-metal ions ensembles. By means of statistical analysis methods, the as-developed array is shown excellent capabilities in the detection and discrimination of phosphate anions. Furthermore, practicability of the sensor array is validated by the successful identification of phosphates in serum and blind samples. Compared to previous reports, the as-developed multichannel sensor array manifests numerous advantages, such as simple fabrication process, flexible adjusting detection ranges, and possible extension to other analytes having similar chemical structures or properties.
Co-reporter:Kai Jiang, Yuhui Wang, Congzhong Cai, and Hengwei Lin
Chemistry of Materials June 13, 2017 Volume 29(Issue 11) pp:4866-4866
Publication Date(Web):May 5, 2017
DOI:10.1021/acs.chemmater.7b00831
The achievement of long afterglow in aqueous solution and as well as with small effects of dissolved oxygen is critical for its applications, but this is still a highly difficult and challenging task. Herein, a novel strategy for facilely preparing room temperature long afterglow material is reported via covalently fixing carbon dots (CDs) onto colloidal nanosilica (nSiO2). The as-obtained materials (named m-CDs@nSiO2) show not only an unexpected long afterglow emission in water dispersion (lifetime as high as 0.703 s) but also with small effects of the dissolved oxygen. Further studies revealed that the observed long afterglow of m-CDs@nSiO2 possesses a predominant delayed fluorescence nature and mixed with a portion of phosphorescence. Some key knowledge that can be concluded from this study are (i) covalent interaction could be employed as an option to fix and rigidify triplet emission species; (ii) covalent bonds fixation strategy could behave as a better alternative than that of the frequently used hydrogen/halogen bonds for stabilizing triplets, because this benefits in extending the occurrence of long afterglow from only solid to solution/dispersion forms; and (iii) the containing unsaturated bonds (e.g., C═C) on the surface of CDs make them to be self-protection agents from the usual quenching effects of oxygen to the triplets due to their capabilities of reaction with oxygen during the irradiation process. On the basis of the unique long afterglow features of m-CDs@nSiO2 in water dispersion and oxygen insensitivity, a moisture-related strategy for high-level information protection is proposed and demonstrated.
Co-reporter:Xiaoxue Wu, Shan Sun, Yuhui Wang, Jiali Zhu, Kai Jiang, Yumin Leng, Qinghai Shu, Hengwei Lin
Biosensors and Bioelectronics 2017 Volume 90(Volume 90) pp:
Publication Date(Web):15 April 2017
DOI:10.1016/j.bios.2016.10.060
•A fluorescent carbon-dots-based nanoprobe for peroxynitrite sensingin mitochondria is developed.•The nanoprobe shows high sensitivity and selectivity towards peroxynitrite.•The nanoprobe exhibits excellent biocompatibility and can be applied for peroxynitrite sensing in mitochondria.•The carbon-dots can serve as promising nanocarriers for fabricating other organelle-targetable nanoprobes.Mitochondria, the power generators in cell, are a primary organelle of oxygen consumption and a main source of reactive oxygen/nitrogen species (ROS/RNS). Peroxynitrite (ONOO−), known as a kind of RNS, has been considered to be a significant factor in many cell-related biological processes, and there is great desire to develop fluorescent probes that can sensitively and selectively detect peroxynitrite in living cells. Herein, we developed a fluorescent carbon-dots (C-dots) based mitochondria-targetable nanoprobe with high sensitivity and selectivity for peroxynitrite sensing in living cells. The C-dots with its surface rich in amino groups was synthesized using o-phenylenediamine as carbon precursor, and it could be covalently conjugated with a mitochondria-targeting moiety, i.e. triphenylphosphonium (TPP). In the presence of peroxynitrite, the fluorescence of the constructed nanoprobe (C-dots-TPP) was efficiently quenched via a mechanism of photoinduced electron transfer (PET). The nanoprobe exhibited relatively high sensitivity (limit of detection: 13.5 nM) and selectivity towards peroxynitrite in aqueous buffer. The performance of the nanoprobe for fluorescence imaging of peroxynitrite in mitochondria was investigated. The results demonstrated that the nanoprobe showed fine mitochondria-targeting ability and imaging contrast towards peroxynitrite in living cells. We anticipate that the proposed nanoprobe will provide a facile tool to explore the role played by peroxynitrite in cytobiology.
Co-reporter:Liling Ma;Shan Sun;Yuhui Wang;Kai Jiang;Jiali Zhu;Jun Li
Microchimica Acta 2017 Volume 184( Issue 10) pp:3833-3840
Publication Date(Web):11 July 2017
DOI:10.1007/s00604-017-2412-z
The authors describe a fluorometric nanoprobe for hypochlorite ion. It was prepared by covalently linking o-phenylenediamine to graphene quantum dots (GQDs). The probe displays green fluorescence with excitation/emission peaks at 440/534 nm. In the presence of chlorite, oPD is oxidized to form a quinone-iminium compound which induces a reduction in fluorescence intensity. The nanoprobe enables chlorite to be determined with a 69 nM limit of detection. The probe is highly selective, well water soluble and biocompatible. It was successfully employed in the determination of chlorite in spiked tap water and living cells. The method is believed to represent a promising tool for the determination of chlorite in environmental, biological and clinical samples.
Co-reporter:Yan Zhao, Xiaolong Wu, Shan Sun, Liling Ma, Ling Zhang, Hengwei Lin
Carbon 2017 Volume 124(Volume 124) pp:
Publication Date(Web):1 November 2017
DOI:10.1016/j.carbon.2017.09.011
A facile and high-efficient approach for the preparation of graphene quantum dots (GQDs) is reported. With the assistance of KO2 in the hydrothermal cutting graphene oxide (GO), a conversion rate of ∼35 wt% from GO to GQDs is achieved. The as-prepared GQDs display rarely observed yellow emissive photoluminescence with a respectable quantum yield of 8.9% in H2O. Moreover, the GQDs are further demonstrated to perform as a potential pH probe and bioimaging agent.Download high-res image (278KB)Download full-size image
Co-reporter:Jiali Zhu, Shan Sun, Kai Jiang, Yuhui Wang, Wenqing Liu, Hengwei Lin
Biosensors and Bioelectronics 2017 Volume 97(Volume 97) pp:
Publication Date(Web):15 November 2017
DOI:10.1016/j.bios.2017.05.054
•A nanoprobe based on PET from ferrocene to carbon dots is constructed.•The nanoprobe exhibits high sensitivity (2.9 nM) and good selectivity towards peroxynitrite.•The PET process is clearly verified by the theory of HOMO-LUMO.•The nanoprobe has been adopted for intracellular peroxynitrite sensing.Herein, a highly sensitive and selective fluorimetric nanoprobe for peroxynitrite (ONOO−) detection based on photoinduced electron transfer (PET) from ferrocene (Fc) to carbon dots (CDs) is reported. The nanoprobe (named CDs-Fc) can be facilely constructed through covalently conjugating CDs and ferrocenecarboxylic acid. Further studies reveal that the energy level of highest occupied molecular orbital (HOMO) of the CDs is lowered with the addition of ONOO− due to its oxidation and nitration capabilities. Thus, an efficient electron transfer from Fc to the excited states of CDs could occur, leading to obvious fluorescence quenching. The fluorescence quenching of the nanoprobe was determined to be peroxynitrite concentrations dependence with a linear range between 4 nM to 0.12 μM. Thanks to the excellent optical properties of the CDs and efficient electron transfer efficiency from Fc to the excited CDs, the nanoprobe exhibits very high sensitivity to ONOO− with a limit of detection (LOD) of 2.9 nM. To the best of our knowledge, this LOD is the highest reported value till today for the detection of peroxynitrite. Besides, the nanoprobe also shows excellent selectivity to ONOO− among a broad range of substances, even including other reactive oxygen/nitrogen species (ROS/RNS). Finally, the nanoprobe was verified to be very low cytotoxicity, and was successfully applied for intracellular ONOO− detection. This work would provide a promising tool for the research of ONOO− in cytobiology and disease diagnosis.
Co-reporter:Xun Lv, Ling Zhang, Feifei Xing, Hengwei Lin
Microporous and Mesoporous Materials 2016 Volume 225() pp:238-244
Publication Date(Web):1 May 2016
DOI:10.1016/j.micromeso.2015.12.024
•Performed systematic studies to investigate the effects of synthetic parameters on the size of MSNs.•MSNs with adjustable size from 20 to 110 nm were obtained.•A possible formation mechanism of MSNs was proposed.•The diameters of MSNs were dependent on the concentration of silica-surfactant micelles.In this work, systematic studies were performed to investigate the effects of experimental parameters (e.g. reaction temperature, stirring rate and concentration of triethanolamine (TEA)) on the particle sizes of mesoporous silica nanoparticles (MSNs). Results revealed that the stirring rate played a key role in the size-controlling of MSNs. Additionally, both the reaction temperature and the concentration of TEA showed relatively obvious influence on the sizes of MSNs. We supposed that the MSNs particles were formed by the aggregation and condensing of silica-surfactant micelles and the diameters of MSNs were dependent on the concentration of silica-surfactant micelles. In order to obtain MSNs with small sizes, low reaction temperature and rapid stirring rate were adopted to reduce the concentration of silica-surfactant micelles and suppress the growth of MSNs. As a surface capping ligand, TEA could suppress the particle growth and prevent the particle aggregation of MSNs. By simply controlling the synthetic parameters, MSNs with adjustable size from 20 to 110 nm were obtained. Moreover, the obtained MSNs displayed narrow size distribution and well dispersity in water, which made them highly promising in biomedical applications.
Co-reporter:Sihua Qian, Yumin Leng and Hengwei Lin
RSC Advances 2016 vol. 6(Issue 10) pp:7902-7907
Publication Date(Web):13 Jan 2016
DOI:10.1039/C5RA25805G
Colorimetric sensor arrays demonstrate numerous superior features in chemo- and bio-sensing, but they are generally not applicable to less-reactive analytes. Based on the findings that N-methyl carbamate pesticides could be decomposed into reactive phenols in basic media, herein, a novel strategy of strong base pre-treatment was developed and employed for the colorimetric sensor array detection and differentiation of the N-methyl carbamate pesticides in an indirect manner. With the use of five inexpensive and commercially available phenol responsive indicators, such a colorimetric sensor array can be facilely fabricated. Classification analysis (e.g. hierarchical clustering analysis (HCA) and principal component analysis (PCA)) reveals that the as-fabricated sensor array has an extremely high dimensionality and, consequently, exhibits excellence in discriminating a variety of N-methyl carbamates from other types of pesticides and potential interferants, and further identifying them exactly from each other. Moreover, semi-quantitative detection could also be achieved through combining HCA/PCA, recognition patterns, and corresponding fitting curves. Overall, the as-developed method exhibits high selectivity and sensitivity, good anti-interference, simultaneous detection and identification capability for each of the N-methyl carbamate pesticides, and potential applicability in real samples. Most importantly, this study demonstrates that pre-treatment strategies are very effective in expanding the range of applications of colorimetric sensor array methodology to less-reactive analytes.
Co-reporter:Kai Jiang;Dr. Ling Zhang;Junfeng Lu; Chunxiang Xu; Congzhong Cai; Hengwei Lin
Angewandte Chemie International Edition 2016 Volume 55( Issue 25) pp:
Publication Date(Web):
DOI:10.1002/anie.201603822
Co-reporter:Shan Sun, Ling Zhang, Kai Jiang, Aiguo Wu, and Hengwei Lin
Chemistry of Materials 2016 Volume 28(Issue 23) pp:
Publication Date(Web):November 10, 2016
DOI:10.1021/acs.chemmater.6b03695
The achievement of high-efficient pure red emissive carbon dots (CDs) is still a great challenge as well as one of the most critical issues that hinders widespread applications of CDs. Herein, a facile approach for the preparation of high-efficient red emissive CDs (R-CDs) is reported, and they exhibit numerous unique features including pure red emission (λmax ≈ 640 nm), respectable quantum yield (22.9%), low cytotoxicity, two-photon excited fluorescence (TPEF), and high photothermal conversion efficiency (43.9% under irradiation of 671 nm laser). Moreover, the chemical composition and photophysical properties of the R-CDs are detailed characterized and analyzed, and from which their photoluminescence mechanism is proposed. Interestingly, the R-CDs are found to particularly light up RNA-rich nucleolus both in one-photon and two-photon modes as well as show excellent counterstain compatibilities with other classical subcellular dyes. The localization of the R-CDs in nucleolus is supported by ribonuclease digestion testing, and the stronger emission is further verified to be due to an accumulation process. In addition, the R-CDs are confirmed to be facilely conjugated with fluorescein isothiocyanate (FITC) and then bring it into living cells, which reveals their potentials to perform as carriers for delivery of drugs that cannot (or hardly) enter into living cells directly. Finally, the R-CDs are shown to be excellent in photothermal cancer therapy in vitro due to their high photothermal conversion efficiency. This study represents not only a facile method for the preparation of high-efficient R-CDs, but also opens many possibilities for applications, such as in biomedicine (multifunctional theranostic agents) and emitting/display devices, thanks to their unique and superior properties.
Co-reporter:Li Liu;Yumin Leng
Microchimica Acta 2016 Volume 183( Issue 4) pp:1367-1373
Publication Date(Web):2016 April
DOI:10.1007/s00604-016-1777-8
The authors report on a colorimetric method for the determination of Cr(VI) using gold nanoparticles (AuNPs) modified with the reagent 1,5-diphenylcarbazide (DPC). The detection scheme is based on the well-known redox reaction that occurs between DPC (on the AuNPs) and Cr(VI) ion, this followed by complexation between oxidized DPC and Cr(III). This complexation then triggers aggregation of the AuNPs and a color change from red to blue. The method is highly selective for Cr(VI) and has a 0.3 μM limit of detection which is much lower than the maximal permitted level in drinking water (i.e. ~1 μM) as regulated by the Chinese Ministry of Environmental Protection. The assay was applied to the rapid determination of Cr(VI) in real environmental water and seafood samples.
Co-reporter:Kai Jiang;Dr. Ling Zhang;Junfeng Lu; Chunxiang Xu; Congzhong Cai; Hengwei Lin
Angewandte Chemie 2016 Volume 128( Issue 25) pp:
Publication Date(Web):
DOI:10.1002/ange.201603822
Co-reporter:Kai Jiang;Dr. Ling Zhang;Junfeng Lu; Chunxiang Xu; Congzhong Cai; Hengwei Lin
Angewandte Chemie 2016 Volume 128( Issue 25) pp:7347-7351
Publication Date(Web):
DOI:10.1002/ange.201602445
Abstract
Photoluminescence (PL), up-conversion PL (UCPL), and phosphorescence are three kinds of phenomena common to light-emitting materials, but it is very difficult to observe all of them simultaneously when they are derived from a single material at room temperature. For the first time, triple-mode emission (that is, PL, UCPL, and room temperature phosphorescence (RTP)) is reported, which relies on a composite of the luminescent carbon dots (CDs) prepared from m-phenylenediamine and poly(vinyl alcohol) (PVA). Moreover, the CDs-PVA aqueous dispersion is nearly colorless and demonstrates promise as a triple-mode emission ink in the field of advanced anti-counterfeiting.
Co-reporter:Kai Jiang;Dr. Ling Zhang;Junfeng Lu; Chunxiang Xu; Congzhong Cai; Hengwei Lin
Angewandte Chemie International Edition 2016 Volume 55( Issue 25) pp:7231-7235
Publication Date(Web):
DOI:10.1002/anie.201602445
Abstract
Photoluminescence (PL), up-conversion PL (UCPL), and phosphorescence are three kinds of phenomena common to light-emitting materials, but it is very difficult to observe all of them simultaneously when they are derived from a single material at room temperature. For the first time, triple-mode emission (that is, PL, UCPL, and room temperature phosphorescence (RTP)) is reported, which relies on a composite of the luminescent carbon dots (CDs) prepared from m-phenylenediamine and poly(vinyl alcohol) (PVA). Moreover, the CDs-PVA aqueous dispersion is nearly colorless and demonstrates promise as a triple-mode emission ink in the field of advanced anti-counterfeiting.
Co-reporter:Lulu Pan;Shan Sun;Aidi Zhang;Kai Jiang;Ling Zhang;Chaoqing Dong;Qing Huang;Aiguo Wu
Advanced Materials 2015 Volume 27( Issue 47) pp:7782-7787
Publication Date(Web):
DOI:10.1002/adma.201503821
Co-reporter:Yuhui Wang, Kai Jiang, Jiali Zhu, Ling Zhang and Hengwei Lin
Chemical Communications 2015 vol. 51(Issue 64) pp:12748-12751
Publication Date(Web):30 Jun 2015
DOI:10.1039/C5CC04905A
A novel FRET-based sensing platform employing fluorescent carbon dots and MnO2 nanosheets as energy donor–acceptor pairs is designed and fabricated for the first time, which demonstrates a promising application for the detection of glutathione in human whole blood samples with high sensitivity.
Co-reporter:Kai Jiang, Shan Sun, Ling Zhang, Yuhui Wang, Congzhong Cai, and Hengwei Lin
ACS Applied Materials & Interfaces 2015 Volume 7(Issue 41) pp:23231
Publication Date(Web):October 1, 2015
DOI:10.1021/acsami.5b07255
Fluorescent carbon dots (CDs) have attracted much attention in recent years because of their superior optical and chemical properties, thus demonstrating many potential applications. However, the previously reported CDs mostly show strong emission only in the blue-light region, and the long-wavelength (i.e., yellow- to red-light) emissions are usually very weak. Such a drawback restricts their further applications, particularly in the biology-relevant fields. Herein, a rare example of N-doped CDs that emit bright-yellow fluorescence (i.e., y-CDs) is reported using 1,2,4-triaminobenzene as carbon precursor. The as-prepared y-CDs exhibit not only respectable emission quantum yield and highly optical stabilities but superior biocompatibility and biolabeling potentials. In addition, the y-CDs are found to show an interesting “ON–OFF–ON” three-state emission with the stepwise addition of Ag+ and cysteine (Cys), indicating potential applications as a bifunctional sensing platform. Thanks to the highly intense emission of y-CDs, the gradual quenching and restoration of their fluorescence with the addition of Ag+ and further Cys could also be observed with the naked eye. More importantly, the ensemble of the y-CDs and Ag+ demonstrates practicability for the highly selective and sensitive detection of Cys in human plasma samples with satisfactory results.Keywords: bifunctional sensing; bioimaging; carbon dots; N-doping; yellow emission
Co-reporter:Sihua Qian and Hengwei Lin
Analytical Chemistry 2015 Volume 87(Issue 10) pp:5395
Publication Date(Web):April 27, 2015
DOI:10.1021/acs.analchem.5b00738
Due to relatively low persistence and high effectiveness for insect and pest eradication, organophosphates (OPs) and carbamates are the two major classes of pesticides that broadly used in agriculture. Hence, the sensitive and selective detection of OPs and carbamates is highly significant. In this current study, a colorimetric sensor array comprising five inexpensive and commercially available thiocholine and H2O2 sensitive indicators for the simultaneous detection and identification of OPs and carbamates is developed. The sensing mechanism of this array is based on the irreversible inhibition capability of OPs and carbamates to the activity of acetylcholinesterase (AChE), preventing production of thiocholine and H2O2 from S-acetylthiocholine and acetylcholine and thus resulting in decreased or no color reactions to thiocholine and H2O2 sensitive indicators. Through recognition patterns and standard statistical methods (i.e., hierarchical clustering analysis and principal component analysis), the as-developed array demonstrates not only discrimination of OPs and carbamates from other kinds of pesticides but, more interestingly, identification of them exactly from each other. Moreover, this array is experimentally confirmed to have high selectivity and sensitivity, good anti-interference capability, and potential applications in real samples for OPs and carbamates.
Co-reporter:Kai Jiang;Shan Sun;Dr. Ling Zhang;Yue Lu; Aiguo Wu; Congzhong Cai; Hengwei Lin
Angewandte Chemie International Edition 2015 Volume 54( Issue 18) pp:5360-5363
Publication Date(Web):
DOI:10.1002/anie.201501193
Abstract
A facile approach for preparation of photoluminescent (PL) carbon dots (CDs) is reported. The three resulting CDs emit bright and stable red, green and blue (RGB) colors of luminescence, under a single ultraviolet-light excitation. Alterations of PL emission of these CDs are tentatively proposed to result from the difference in their particle size and nitrogen content. Interestingly, up-conversion (UC)PL of these CDs is also observed. Moreover, flexible full-color emissive PVA films can be achieved through mixing two or three CDs in the appropriate ratios. These CDs also show low cytotoxicity and excellent cellular imaging capability. The facile preparation and unique optical features make these CDs potentially useful in numerous applications such as light-emitting diodes, full-color displays, and multiplexed (UC)PL bioimaging.
Co-reporter:Kai Jiang;Shan Sun;Dr. Ling Zhang;Yue Lu; Aiguo Wu; Congzhong Cai; Hengwei Lin
Angewandte Chemie 2015 Volume 127( Issue 18) pp:5450-5453
Publication Date(Web):
DOI:10.1002/ange.201501193
Abstract
A facile approach for preparation of photoluminescent (PL) carbon dots (CDs) is reported. The three resulting CDs emit bright and stable red, green and blue (RGB) colors of luminescence, under a single ultraviolet-light excitation. Alterations of PL emission of these CDs are tentatively proposed to result from the difference in their particle size and nitrogen content. Interestingly, up-conversion (UC)PL of these CDs is also observed. Moreover, flexible full-color emissive PVA films can be achieved through mixing two or three CDs in the appropriate ratios. These CDs also show low cytotoxicity and excellent cellular imaging capability. The facile preparation and unique optical features make these CDs potentially useful in numerous applications such as light-emitting diodes, full-color displays, and multiplexed (UC)PL bioimaging.
Co-reporter:Huangxin Zhou, Xun Lv, Ling Zhang, An Gong, Aiguo Wu, Zhenhua Liang, Guihua Peng and Hengwei Lin
Journal of Materials Chemistry A 2014 vol. 2(Issue 45) pp:9625-9630
Publication Date(Web):29 Sep 2014
DOI:10.1039/C4TC02163K
A facile approach for the synthesis of fluorescent mesoporous silica (FMS) is reported. The FMS could be achieved in situ through a mild hydrothermal reaction between easily obtained 3-(2-aminoethylamino) propyltrimethoxysilane functionalized SBA-15 and citric acid. This resulting material shows strong and stable fluorescence while preserving good mesoporous structures. The developed approach is simple and has a potential to be applied for scaled-up preparation. Importantly, the resulted FMS exhibit simultaneous Hg2+ detection and removal properties, low cytotoxicity and excellent cell imaging capability. These advantageous features demonstrate many potential applications such as in sensing and adsorption of contaminants, bioimaging, drug delivery and tracking.
Co-reporter:Li Liu and Hengwei Lin
Analytical Chemistry 2014 Volume 86(Issue 17) pp:8829
Publication Date(Web):July 29, 2014
DOI:10.1021/ac5021886
A novel approach is presented in this article to qualitatively and semiquantitatively analyze multiple heavy metal ions simultaneously by a colorimetric array test strip. As a proof-of-concept application, a multi-ion analysis array test strip (for Hg2+, Ag+, and Cu2+) was fabricated through immobilizing five specifically responsive indicators in typical matrixes with tunable sensitivities. The as-obtained test strip shows not only high selectivity for Hg2+, Ag+, and Cu2+, respectively, but also can be applied for their mixtures. The detection limit of the test strip is well below the Chinese wastewater discharge standard concentrations. Moreover, the array test strip demonstrates excellent anti-interference capability, detection, and production reproducibility, long-term storage stability, and real water sample applicability.
Co-reporter:Huangxin Zhou, Ling Zhang, Zhenhua Liang, Guihua Peng, Hengwei Lin
Dyes and Pigments 2014 Volume 111() pp:52-57
Publication Date(Web):December 2014
DOI:10.1016/j.dyepig.2014.05.034
•Immobilization of a non-aqueous soluble Hg2+ probe onto mesoporous silica was achieved.•The immobilized probe exhibited enhanced sensitivity and selectivity for Hg2+ detection.•Immobilization of a non-aqueous soluble probe onto mesoporous silica can extend its application to pure aqueous media.•The as-prepared material exhibits a high adsorption capacity for Hg2+.•The developed method may be readily extended to other sensing systems.An efficient strategy to immobilize a non-aqueous soluble Hg2+ probe onto mesoporous silica is developed, and this immobilization is subject to several advantages regarding Hg2+ detection, such as improving sensing sensitivity and selectivity, extending application from an organic/aqueous mixture to a pure aqueous medium, and achieving removal of Hg2+ ions while detection. The selected Hg2+ probe, rhodamine B thiohydrazide, can be readily covalently immobilized onto mesoporous silica through a simple amide reaction and subsequently exhibits more than 10 times enhancement of sensitivity for Hg2+ (limits of detection are of 0.81 ppb in immobilized form versus 10 ppb in free form), and an adsorption capacity of 192 mg/g. Brunauer–Emmett–Teller and TEM characterizations demonstrate that the mesoporous structure can be well remained after Hg2+ probe modification and this feature is believed to be responsible for improved Hg2+ sensing properties.Immobilization of a non-aqueous soluble Hg2+ probe onto mesoporous silica SBA-15 was developed, which exhibited improved sensing performance for Hg2+ than that of the free form in solution and expanded its applicability in pure water. Meanwhile, the modified SBA-15 showed high adsorption capacity for Hg2+ as well.
Co-reporter:Sihua Qian and Hengwei Lin
RSC Advances 2014 vol. 4(Issue 56) pp:29581-29585
Publication Date(Web):16 Jun 2014
DOI:10.1039/C4RA05004E
A very facile approach for the design and fabrication of a colorimetric sensor array, by using only a single indicator–receptor couple at various ratios and concentrations, is described for the first time. As a proof-of-concept application, discrimination and identification of the 20 natural amino acids has been successfully accomplished. Classification analyses demonstrate that the as-fabricated colorimetric sensor array has a high dimensionality and, consequently, has the capability to recognize the 20 natural amino acids. Moreover, the amino acids can be qualitatively and semi-quantitatively detected by combining classification analyses, recognition patterns and corresponding fitting curves. The strategy developed in the current study likely represents a “maximally” simplified approach for design and fabrication of colorimetric sensor arrays, and could be taken full advantage of among investigators in the sensing application field.
Co-reporter:Yue Lu;Dr. Ling Zhang; Hengwei Lin
Chemistry - A European Journal 2014 Volume 20( Issue 15) pp:4246-4250
Publication Date(Web):
DOI:10.1002/chem.201304358
Abstract
A microreactor is applied and reported, for the first time, in the field of research of carbon dots (CDs), including rapid screening of the reaction conditions and investigation of the photoluminescence (PL) mechanism. Various carbonaceous precursors and solvents were selected and hundreds of reaction conditions were screened (ca. 15 min on average per condition). Through analyzing the screened conditions, tunable PL emission maxima, from about 330 to 550 nm with respectable PL quantum yields, were achieved. Moreover, the relationship between different developmental stages of the CDs and the PL properties was explored by using the microreactor. The PL emission was observed to be independent of the composition, carbonization extent, and morphology/size of the CDs. This study unambiguously presents that a microreactor could serve as a promising tool for the research of CDs.
Co-reporter:Sihua Qian
Analytical and Bioanalytical Chemistry 2014 Volume 406( Issue 7) pp:1903-1908
Publication Date(Web):2014 March
DOI:10.1007/s00216-013-7591-9
A simple, inexpensive yet highly selective colorimetric indicator-displacement assay array for the simultaneous detection and identification of three important biothiols at micromolar concentrations under physiological conditions and in real samples has been developed in this work. With use of an array composed of metal indicators and metal ions, clear differentiation among cysteine, homocysteine and glutathione was achieved. On the basis of the colour change of the array, quantification of each analyte was accomplished easily, and different biothiols were identified readily using standard chemometric approaches (hierarchical clustering analysis). Moreover, the colorimetric sensor array was not responsive to changes with 19 other natural amino acids, and it showed excellent reproducibility. Importantly, the sensor array developed was successfully applied to the determination and identification of the three biothiols in a real biological sample.
Co-reporter:Huangxin Zhou, Xun Lv, Ling Zhang, An Gong, Aiguo Wu, Zhenhua Liang, Guihua Peng and Hengwei Lin
Journal of Materials Chemistry A 2014 - vol. 2(Issue 45) pp:NaN9630-9630
Publication Date(Web):2014/09/29
DOI:10.1039/C4TC02163K
A facile approach for the synthesis of fluorescent mesoporous silica (FMS) is reported. The FMS could be achieved in situ through a mild hydrothermal reaction between easily obtained 3-(2-aminoethylamino) propyltrimethoxysilane functionalized SBA-15 and citric acid. This resulting material shows strong and stable fluorescence while preserving good mesoporous structures. The developed approach is simple and has a potential to be applied for scaled-up preparation. Importantly, the resulted FMS exhibit simultaneous Hg2+ detection and removal properties, low cytotoxicity and excellent cell imaging capability. These advantageous features demonstrate many potential applications such as in sensing and adsorption of contaminants, bioimaging, drug delivery and tracking.
Co-reporter:Yuhui Wang, Kai Jiang, Jiali Zhu, Ling Zhang and Hengwei Lin
Chemical Communications 2015 - vol. 51(Issue 64) pp:NaN12751-12751
Publication Date(Web):2015/06/30
DOI:10.1039/C5CC04905A
A novel FRET-based sensing platform employing fluorescent carbon dots and MnO2 nanosheets as energy donor–acceptor pairs is designed and fabricated for the first time, which demonstrates a promising application for the detection of glutathione in human whole blood samples with high sensitivity.
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![Spiro[1H-isoindole-1,9'-[9H]xanthen]-3(2H)-one, 2-amino-3',6'-bis(diethylamino)-](/data/chemimg/659200/74317-53-6.png)
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