Co-reporter:Ben Shi, Xianfeng Gu, Zhijun Wang, Ge Xu, Qiang Fei, Jie Tang, and Chunchang Zhao
ACS Applied Materials & Interfaces October 18, 2017 Volume 9(Issue 41) pp:35588-35588
Publication Date(Web):September 28, 2017
DOI:10.1021/acsami.7b11226
Probes bearing good aqueous solubility and biocompatibility as well as fast response can serve as ideal tools for evaluating the underlying molecular mechanism of endogenous production of H2S caused by drugs; however, they are still lacking but highly desirable. Here, we demonstrate a novel strategy for constructing highly efficient H2S nanoprobes through locking Förster resonance energy transfer borondipyrromethene (BODIPY) pairs in water-dispersible core–shell silica nanoparticles. Importantly, these nanocomposites can effectively confine complementary guests within the same cores due to the existence of a shield, thus guaranteeing efficient Förster resonance energy transfer. Interestingly, the interior microenvironment of such nanoparticles could be tuned by silylation agents. In this way, an ideal probe for rapid and ratiometric detection of H2S within 15 s is established by optimizing the amount of silylation agent with a polar organic group. Obviously, the silylation agents are explored to serve as a platform not only for establishment of robust structures but also for optimizing the microenvironment of the interior to afford an ideal probe. These silica nanocomposites have also been successfully employed in disclosing the endogenous production of H2S induced by estrogen in cardiomyocytes.Keywords: endogenous H2S; fast response; fluorescent probes; robust; silica nanocomposites;
Co-reporter:Zhe Zhou, Feiyi Wang, Guichun Yang, Cuifen Lu, Junqi Nie, Zuxing Chen, Jun Ren, Qi Sun, Chunchang Zhao, and Wei-Hong Zhu
Analytical Chemistry November 7, 2017 Volume 89(Issue 21) pp:11576-11576
Publication Date(Web):October 10, 2017
DOI:10.1021/acs.analchem.7b02910
Leucine aminopeptidase (LAP) is an important cancer-related biomarker, which shows significant overexpression in malignant tumor cells like liver cancer. Developing an effective method to monitor LAP in tumor cells holds great potential for cancer diagnosis, treatment, and management. In this work, we report a novel BODIPY-based fluorescent probe (BODIPY-C-Leu) capable of monitoring LAP in vitro and in vivo in both ratiometric and turn-on model. BODIPY-C-Leu contains an asymmetrical BODIPY dye for fluorescent signaling and a dipeptide (Cys-Leu) as the triggered moiety. Activation occurs by cleavage of the amide bond in dipeptides and subsequently an intramolecular S → N conversion to convert sulfur-substituted BODIPY to amino-substituted BODIPY, resulting in a dramatic fluorescence variation to realize the detection of LAP. Furthermore, we have successfully employed BODIPY-C-Leu to monitor LAP activity in different cancer cells, indicating that HeLa cells have a higher level of LAP activity than A549 cells. Importantly, we demonstrated the capability of the probe for real-time monitoring the drug-induced LAP level changes in zebrafish.
Co-reporter:Qiang Fei;Xianfeng Gu;Yajing Liu;Ben Shi;Hengyan Liu;Ge Xu;Chunbao Li;Ping Shi
Organic & Biomolecular Chemistry 2017 vol. 15(Issue 19) pp:4072-4076
Publication Date(Web):2017/05/16
DOI:10.1039/C7OB00383H
Novel BODIPYs undergoing excited state intramolecular proton transfer are reported. The molecules afford NIR emission with a large Stokes shift and possess a free hydroxyl unit that is easy to functionalize, allowing the dyes to be exploited as a valuable scaffold in probe design.
Co-reporter:Ben Shi;Xianfeng Gu;Qiang Fei
Chemical Science (2010-Present) 2017 vol. 8(Issue 3) pp:2150-2155
Publication Date(Web):2017/02/28
DOI:10.1039/C6SC04703C
H2S is a key chemical mediator that exerts a vital role in diverse physiological and pathological processes. However, in vivo tracking of endogenous H2S generation still remains difficult due to the lack of reliable analytical methods. Herein, we present the first example of activatable photoacoustic probes for real-time imaging of H2S in living mice through the full utilization of the superiority of photoacoustic imaging modality at fine spatial resolution during deep tissue penetration. The designed probe can generate high NIR absorption at 780 nm in the presence of H2S, thus producing a strong photoacoustic signal output in the NIR region. Furthermore, this probe exhibits extremely fast and highly selective responsiveness, good water-solubility and excellent biocompatibility. In light of these outstanding features, this probe realizes the direct photoacoustic trapping of endogenous H2S generation in a HCT116 tumor-bearing mouse model. These preliminary imaging studies show that HCT116 colon tumors exhibit CBS upregulation activity, resulting in an increased rate of H2S generation.
Co-reporter:Jie Tian;Qinglong Yan;Ying Zhu;Jichao Zhang;Jiao Li;Ben Shi;Ge Xu;Chunhai Fan
Chinese Journal of Chemistry 2017 Volume 35(Issue 11) pp:1711-1716
Publication Date(Web):2017/11/01
DOI:10.1002/cjoc.201700248
A fluorescent turn-on probe for specifically targeting γ-glutamyltranspeptidase (GGT) was designed and synthesized by integrating boron-dipyrromethene (BODIPY) as a chromophore and glutathione (GSH) as the GGT substrate. GGT-catalyzed the cleavage of the γ-glutamyl bond and generated the aromatic hydrocarbon transfer between the sulfur and the nitrogen atom in BODIPY, leading to distinct optical changes. Such specific responsiveness provides an easily distinguishable fluorescence signal to visualize the GGT activity in living cells and differentiate GGT-positive cancer cells from GGT-negative cells.
Co-reporter:Chunchang Zhao, Jiancai An, Li Zhou, Qiang Fei, Feiyi Wang, Jie Tan, Ben Shi, Rui Wang, Zhiqian Guo and Wei-Hong Zhu
Chemical Communications 2016 vol. 52(Issue 10) pp:2075-2078
Publication Date(Web):01 Dec 2015
DOI:10.1039/C5CC08936K
Two novel probes were designed, sharing the same BODIPY core but differing only by a minimized variation in the recognition site from 4-hydroxyaniline into 4-methoxyaniline. Such a small change in the reaction site could switch the selective detection from peroxynitrite to HOCl. Undoubtedly, the new designed BODIPY core exhibits valuable properties.
Co-reporter:Xuzhe Wang, Li Zhou, Fei Qiang, Feiyi Wang, Rui Wang, Chunchang Zhao
Analytica Chimica Acta 2016 Volume 911() pp:114-120
Publication Date(Web):10 March 2016
DOI:10.1016/j.aca.2016.01.022
•A novel probe for HOCl was synthesized and evaluated.•HOCl-promoted rapid transduction of thioether to sulfoxide function.•This probe features a fast and ratiometric detection.•The probe works excellently within a pH range of 4–10.•This probe can be employed to image endogenous HOCl generation.A BODIPY-based ratiometric fluorescent probe for HOCl has been designed based on the transduction of thioether to sulfoxide function. This probe features a marked absorption and emission blue-shift upon the HOCl-promoted rapid transduction, enabling the highly selective and ratiometric detection. In addition, the probe works excellently within a wide pH range of 4–10, addressing the existing pH dependency issue. Living cells studies demonstrate that the probe is cell membrane permeable and can be employed successfully to image endogenous HOCl generation in macrophage cells.A novel thiol-sulfoxide transduction based probe for HOCl was synthesized and evaluated. This probe features fast response, ratiometric detection and pH-independent sensing.
Co-reporter:Sihang Luo, Yingchao Liu, Feiyi Wang, Qiang Fei, Ben Shi, Jiancai An, Chunchang Zhao and Chen-Ho Tung
Analyst 2016 vol. 141(Issue 10) pp:2879-2882
Publication Date(Web):15 Apr 2016
DOI:10.1039/C6AN00369A
A fluorescent probe for fulfilling a lysosome targeting function in hypoxic tumor cells is reported, wherein azoreductase triggers a dramatic fluorescence enhancement and specific imaging of lysosomes in hypoxic cancer cells.
Co-reporter:Chunchang Zhao; Xiuli Zhang; Kaibin Li; Shaojia Zhu; Zhiqian Guo; Lili Zhang; Feiyi Wang; Qiang Fei; Sihang Luo; Ping Shi; He Tian;Wei-Hong Zhu
Journal of the American Chemical Society 2015 Volume 137(Issue 26) pp:8490-8498
Publication Date(Web):June 12, 2015
DOI:10.1021/jacs.5b03248
H2S produced in small amounts by mammalian cells has been identified in mediating biological signaling functions. However, the in situ trapping of endogenous H2S generation is still handicapped by a lack of straightforward methods with high selectivity and fast response. Here, we encapsulate a semi-cyanine-BODIPY hybrid dye (BODInD-Cl) and its complementary energy donor (BODIPY1) into the hydrophobic interior of an amphiphilic copolymer (mPEG-DSPE), especially for building up a ratiometric fluorescent H2S nanoprobe with extraordinarily fast response. A remarkable red-shift in the absorption band with a gap of 200 nm in the H2S response can efficiently switch off the Förster resonance energy transfer (FRET) from BODIPY1 to BODInD-Cl, subsequently recovering the donor fluorescence. Impressively, both the interior hydrophobicity of supramolecular micelles and electron-withdrawing nature of indolium unit in BODInD-Cl can sharply increase aromatic nucleophilic substitution with H2S. The ratiometric strategy based on the unique self-assembled micellar aggregate NanoBODIPY achieves an extremely fast response, enabling in situ imaging of endogenous H2S production and mapping its physiological and pathological consequences. Moreover, the amphiphilic copolymer renders the micellar assembly biocompatible and soluble in aqueous solution. The established FRET-switchable macromolecular envelope around BODInD-Cl and BODIPY1 enables cellular uptake, and makes a breakthrough in the trapping of endogenous H2S generation within raw264.7 macrophages upon stimulation with fluvastatin. This study manifests that cystathione γ-lyase (CSE) upregulation contributes to endogenous H2S generation in fluvastatin-stimulated macrophages, along with a correlation between CSE/H2S and activating Akt signaling pathway.
Co-reporter:Feiyi Wang, Li Zhou, Chunchang Zhao, Rui Wang, Qiang Fei, Sihang Luo, Zhiqian Guo, He Tian and Wei-Hong Zhu
Chemical Science 2015 vol. 6(Issue 4) pp:2584-2589
Publication Date(Web):18 Feb 2015
DOI:10.1039/C5SC00216H
In situ monitoring of intracellular thiol activity in cell growth and function is highly desirable. However, the discriminative detection of glutathione (GSH) from cysteine (Cys) and homocystein (Hcy) and from common amino acids still remains a challenge due to the similar reactivity of the thiol groups in these amino acids. Here we report a novel strategy for selectively sensing GSH by a dual-response mechanism. Integrating two independent reaction sites with a disulfide linker and a thioether function into a fluorescent BODIPY-based chemsensor can guarantee the synergetic dual-response in an elegant fashion to address the discrimination of GSH. In the first synergetic reaction process, the thiol group in GSH, Cys and Hcy induces disulfide cleavage and subsequent intramolecular cyclization to release the unmasked phenol-based BODIPY (discriminating thiol amino acids from other amino acids). In the second synergetic process, upon the substitution of the thioether with the nucleophilic thiolate to form a sulfenyl-BODIPY, only the amino groups of Cys and Hcy, but not that of GSH, undergo a further intramolecular displacement to yield an amino-substituted BODIPY. In this way, we make full use of the kinetically favorable cyclic transition state in the intramolecular rearrangement, and enable photophysical distinction between sulfenyl- and amino-substituted BODIPY for allowing the discriminative detection of GSH over Cys and Hcy and thiol-lacking amino acids under physiological conditions. Moreover, this probe exhibits a distinguishable ratiometric fluorescence pattern generated from the orange imaging channel to the red channel, which proves the differentiation of GSH from Cys and Hcy in living cells.
Co-reporter:Chunchang Zhao;Haifeng Jiang
Chinese Journal of Chemistry 2015 Volume 33( Issue 7) pp:711-716
Publication Date(Web):
DOI:10.1002/cjoc.201500271
Abstract
BODIPY-based fluorescent chemosensors bearing sulfoxide function were designed and evaluated. Thiols triggered sulfoxidesulfide transduction in these probes leads to an obvious red-shift in absorption and dramatic fluorescence enhancement with distinctly ratiometric features, enabling the accurate assay of thiols in living cells.
Co-reporter:Feiyi Wang; Ying Zhu;Li Zhou;Liang Pan;Zhifen Cui;Qiang Fei;Sihang Luo;Dr. Dun Pan; Qing Huang; Rui Wang; Chunchang Zhao; He Tian; Chunhai Fan
Angewandte Chemie International Edition 2015 Volume 54( Issue 25) pp:7349-7353
Publication Date(Web):
DOI:10.1002/anie.201502899
Abstract
γ-Glutamyltranspeptidase (GGT) is a tumor biomarker that selectively catalyzes the cleavage of glutamate overexpressed on the plasma membrane of tumor cells. Here, we developed two novel fluorescent in situ targeting (FIST) probes that specifically target GGT in tumor cells, which comprise 1) a GGT-specific substrate unit (GSH), and 2) a boron–dipyrromethene (BODIPY) moiety for fluorescent signalling. In the presence of GGT, sulfur-substituted BODIPY was converted to amino-substituted BODIPY, resulting in dramatic fluorescence variations. By exploiting this enzyme-triggered photophysical property, we employed these FIST probes to monitor the GGT activity in living cells, which showed remarkable differentiation between ovarian cancer cells and normal cells. These probes represent two first-generation chemodosimeters featuring enzyme-mediated rapid, irreversible aromatic hydrocarbon transfer between the sulfur and nitrogen atoms accompanied by switching of photophysical properties.
Co-reporter:Feiyi Wang; Ying Zhu;Li Zhou;Liang Pan;Zhifen Cui;Qiang Fei;Sihang Luo;Dr. Dun Pan; Qing Huang; Rui Wang; Chunchang Zhao; He Tian; Chunhai Fan
Angewandte Chemie 2015 Volume 127( Issue 25) pp:7457-7461
Publication Date(Web):
DOI:10.1002/ange.201502899
Abstract
γ-Glutamyltranspeptidase (GGT) is a tumor biomarker that selectively catalyzes the cleavage of glutamate overexpressed on the plasma membrane of tumor cells. Here, we developed two novel fluorescent in situ targeting (FIST) probes that specifically target GGT in tumor cells, which comprise 1) a GGT-specific substrate unit (GSH), and 2) a boron–dipyrromethene (BODIPY) moiety for fluorescent signalling. In the presence of GGT, sulfur-substituted BODIPY was converted to amino-substituted BODIPY, resulting in dramatic fluorescence variations. By exploiting this enzyme-triggered photophysical property, we employed these FIST probes to monitor the GGT activity in living cells, which showed remarkable differentiation between ovarian cancer cells and normal cells. These probes represent two first-generation chemodosimeters featuring enzyme-mediated rapid, irreversible aromatic hydrocarbon transfer between the sulfur and nitrogen atoms accompanied by switching of photophysical properties.
Co-reporter:Chunchang Zhao, Xiuai Li, Yang Yang, Jian Cao, Xuzhe Wang, Yanfen Zhang
Dyes and Pigments 2014 Volume 101() pp:130-135
Publication Date(Web):February 2014
DOI:10.1016/j.dyepig.2013.09.032
•Two BODIPYs were physically trapped inside the hydrophobic core of CTAB micelles.•The BODIPY-CTAB assembles display ratiometric optical change within the pH of 4–9.•The pH dependent red/blue optical switch is reversible and repeatable.Two 6-hydroxyindole-based boron-dipyrromethenes (BODIPYs) have poor solubility and remain essentially nonemissive in water. In this paper, they were physically trapped inside the hydrophobic core of cetyltrimethylammonium bromide (CTAB) micelles, while ensuring solubility of the assembly in water. Due to the hydrophobic character of the micelles core, the two BODIPYs become fluorescent in water as they behave in organic solvents. More importantly, these BODIPY-CTAB assembles display distinct ratiometric optical change within the pH window of 4–9 in complete water system, indicating the capability as ratiometric fluorescent pH indicators. Furthermore, the pH dependent red/blue optical switch is reversible and can be repeated for many cycles by alternative exposure to acidic and basic media.
Co-reporter:Feiyi Wang, Jiancai An, Lili Zhang and Chunchang Zhao
RSC Advances 2014 vol. 4(Issue 96) pp:53437-53441
Publication Date(Web):10 Oct 2014
DOI:10.1039/C4RA11167B
It is still a challenge to construct probes for discriminating thiols due to the similar structure and reactivities of thiol-containing molecules. We have here developed a Cys specific probe by utilizing the remarkable difference in reactivity toward Cys, Hcy and GSH. The reaction between the designed probe and Cys produces an amino-substituted BODIPY, giving a yellow fluorescence turn-on response. The response to Hcy or GSH shows a red fluorescence turn-on signal, due to the formation of sulfenyl-substituted BODIPY. These distinct fluorescence turn-on responses allow Cys to be distinguished from Hcy and GSH. This probe was also utilized for detection of Cys in living cells and monitoring cystathionine γ-lyase activity in vitro.
Co-reporter:Chunchang Zhao, Xia Li, Jinxin Zhang
Inorganica Chimica Acta 2014 Volume 412() pp:32-37
Publication Date(Web):1 March 2014
DOI:10.1016/j.ica.2013.11.033
•Two BODIPYs bearing 8-aminoquinoline and sulfur function were developed.•The two dyes display distinct fluorescence enhancement toward Zn2+.•The change in oxidation state of sulfur function (thioether to sulfoxide) has sufficient effect on the response to Zn2+.Two new borondipyrromethene-based probes BODIPY1 and BODIPY2 were synthesized and evaluated. The chelators in the two probes, 8-aminoquinoline (AQ) and sulfur function, coordinate to Zn2+ in a synergic manner, thus the change in oxidation state of sulfur function (thioether to sulfoxide) would have sufficient effect on the photophysical response properties. As expected, both BODIPY1 and BODIPY2 display distinct fluorescence enhancement toward Zn2+. However, BODIPY1 and BODIPY2 show different binding properties. Pb2+ interferes with Zn2+ detection in BODIPY1 while has little influence on the fluorescence of BODIPY2, interfering that change of the oxidation state of the sulfur atom from thioether to sulfoxide benefits the Zn2+-specific fluorescence response.Graphical abstractTwo BODIPYs bearing 8-aminoquinoline and sulfur function were developed. Photophysical evaluation displayed that change of the oxidation state of the sulfur atom from thioether to sulfoxide has sufficient effect on the photophysical response properties.
Co-reporter:Chunchang Zhao, Kaibin Li, Nan Xie, Ming Zhao, Shiqi Peng
Journal of Photochemistry and Photobiology A: Chemistry 2014 290() pp: 72-76
Publication Date(Web):
DOI:10.1016/j.jphotochem.2014.06.009
Co-reporter: Chunchang Zhao;Xiuai Li ;Feiyi Wang
Chemistry – An Asian Journal 2014 Volume 9( Issue 7) pp:1777-1781
Publication Date(Web):
DOI:10.1002/asia.201402043
Abstract
Background autofluorescence from biological systems generally reduces the sensitivity of a fluorescent probe for imaging biological targets. Addressing this challenge requires the development of fluorescent probes that produce emission in the near-infrared region. Herein, we report the design and synthesis of a fluorescent probe that generates an NIR emission with a large Stokes shift upon the selective response to Cys over Hcy and GSH. The probe is designed to consist of two Cys-sensing sites, an acrylate ester and an aldehyde installed ortho to each other. The reaction of the probe with Cys triggers an excited state intramolecular proton transfer process upon photo-excitation, thereby producing an NIR emission with a large Stokes shift. Accordingly, this probe hold great promise for the selective detection of Cys in biological systems. We further demonstrate the capacity of this probe for Cys imaging in living cells.
Co-reporter:Feiyi Wang;Dr. Zhiqian Guo;Xia Li;Xiuai Li ;Dr. Chunchang Zhao
Chemistry - A European Journal 2014 Volume 20( Issue 36) pp:11471-11478
Publication Date(Web):
DOI:10.1002/chem.201403450
Abstract
The simultaneous discrimination of Cys, Hcy, and GSH by a single probe is still an unmet challenge. The design and synthesis of a small molecule probe MeO-BODIPY-Cl (BODIPY=boron dipyrromethene) is presented, which can allow Cys, Hcy, and GSH to be simultaneously discriminated on the basis of three distinct fluorescence turn-on responses. The probe reacts with these thiols to form sulfenyl-substituted BODIPY, which is followed by intramolecular displacement to yield amino-substituted BODIPY. The kinetic rate of the intramolecular displacement reaction determines the observed different sensing behavior. Therefore, the probe responds to Cys, Hcy, and GSH with fluorescence turn-on colors of yellow, yellow and red, and red, respectively. With this promising feature in hand, the probe was successfully used in imaging of Cys, Hcy and GSH in living cells.
Co-reporter:Chunchang Zhao, Jinxin Zhang, Xuzhe Wang and Yanfen Zhang
Organic & Biomolecular Chemistry 2013 vol. 11(Issue 2) pp:372-377
Publication Date(Web):01 Nov 2012
DOI:10.1039/C2OB26791H
In this paper a general procedure for the introduction of pyridone moiety was developed, using a Friedländer reaction, for post-modification of ready-made BODIPY core, from which three pyridone-fused BODIPYs 1, 2 and 3 were generated. This method is complementary to the classical method for obtaining aromatic ring-fused BODIPYs, which begins with the condensation of the corresponding aromatic ring-fused pyrroles. These pyridone-fused BODIPYs are distinctive, possessing favorable photophysical characteristics with strong absorption, high bright orange fluorescence and easy reduction due to the electron-withdrawing effect of the fused pyridone moiety. More important, these BODIPYs bear reactive functions which are applicable in proteins labeling by bioorthogonal chemical reactions.
Co-reporter:Chunchang Zhao, Xuzhe Wang, Jian Cao, Peng Feng, Jinxin Zhang, Yanfen Zhang, Yang Yang, Zhenjun Yang
Dyes and Pigments 2013 Volume 96(Issue 2) pp:328-332
Publication Date(Web):February 2013
DOI:10.1016/j.dyepig.2012.08.026
Two BODIPY dyes bearing a sulfur containing function at the 3-position are reported. The 3-benzylthio compound shows spectroscopic features of the classical BODIPY platform, showing minor solvent dependent spectral shift, a relative small Stokes shift and a high fluorescence quantum yield. Oxidation of the sulfur atom to the sulfoxide leads to a large hypsochromic shift in absorption and emission. We also demonstrated that the sulfoxide derivative can be used as a ratiometric fluorescent chemodosimeter for highly toxic benzenethiols in aqueous media. In this dosimeter the sulfoxide is chemospecifically reduced by benzenethiols to obtain the original oxidation state of the sulfur atom, accompanied with a drastic ratiometric fluorescence response. Furthermore, the probe features excellent selectivity over other competing analytes, moderate signal response times and a good linearity range for quantification. All these features render the sensor suitable for detection of benzenethiols in environmental settings.Highlights► Two BODIPY dyes bearing a sulfur containing function at the 3-position are reported. ► The two dyes show valuable spectroscopic properties. ► The sulfoxide is a ratiometric fluorescent chemodosimeter for benzenethiols. ► The sulfoxide shows excellent selectivity toward benzenethiols. ► The probe exhibits moderate response time and good linearity for quantification.
Co-reporter:Chunchang Zhao, Yanfen Zhang, Xuzhe Wang, Jian Cao
Journal of Photochemistry and Photobiology A: Chemistry 2013 Volume 264() pp:41-47
Publication Date(Web):15 July 2013
DOI:10.1016/j.jphotochem.2013.05.003
Co-reporter:Jian Cao, Chunchang Zhao, Xuzhe Wang, Yanfen Zhang and Weihong Zhu
Chemical Communications 2012 vol. 48(Issue 79) pp:9897-9899
Publication Date(Web):22 Aug 2012
DOI:10.1039/C2CC35080G
Based on 6-hydroxyindole BODIPY with a Schiff-base structure, NIR fluorescence with impressively high selectivity is triggered by deprotonation of the phenol group upon binding with Zn2+ due to the chelation-enhanced fluorescence effect, thus realizing a promising application in bioimaging of Zn2+.
Co-reporter:Chunchang Zhao, Peng Feng, Jian Cao, Xuzhe Wang, Yang Yang, Yulin Zhang, Jinxing Zhang and Yanfen Zhang
Organic & Biomolecular Chemistry 2012 vol. 10(Issue 15) pp:3104-3109
Publication Date(Web):07 Feb 2012
DOI:10.1039/C2OB06980F
Here, we report a new Cu2+-selective fluorescent turn-on probe BODIPY-EP, in which the 2-pyridinecarboxylic acid is connected to a 6-hydroxyindole-based BODIPY platform through an ester linkage. The ester bond of BODIPY-EP is selectively hydrolyzed by the reaction with Cu2+ under mild and neutral conditions to generate BODIPY-OH, showing strong characteristic fluorescence of BODIPY-OH. The favorable features of BODIPY-EP towards Cu2+ include fast response, large fluorescence enhancement and high selectivity. We further demonstrated that the membrane-permeable probe reacts with intracellular Cu2+ and exhibits bright fluorescence in living cells.
Co-reporter:Xuzhe Wang, Jian Cao and Chunchang Zhao
Organic & Biomolecular Chemistry 2012 vol. 10(Issue 24) pp:4689-4691
Publication Date(Web):10 May 2012
DOI:10.1039/C2OB25633A
A novel thiol–sulfoxide reaction based ratiometric probe for benzenethiols was synthesized and evaluated. The probe features a chemospecific reduction over a pH range of 1–10 by benzenethiols with a marked emission color change, enabling the highly selective detection and is promising for applications.
Co-reporter:Chunchang Zhao, Yulin Zhang, Peng Feng and Jian Cao
Dalton Transactions 2012 vol. 41(Issue 3) pp:831-838
Publication Date(Web):17 Nov 2011
DOI:10.1039/C1DT10797F
A borondipyrromethene-based Zn2+ fluorescent probe BODPAQ was designed and synthesized. The chelators in BODPAQ, 2,2′-dipicolylamine (DPA) and 8-aminoquinoline (AQ), coordinate to Zn2+ in a synergic manner. As a result, BODPAQ displays high Zn2+ selectivity with a dramatic enhanced emission accompanied by a notable hypsochromic shift due to the binary inhibition effect of PET and ICT mechanisms, enabling the detection of Zn2+ by both ratiometric and normal turn-on fluorescence methods in acetonitrile. Interestingly, the sensitivity of BODPAQ towards Zn2+ changes upon varying the compositions of buffer solutions. In 3-morpholinopropanesulfonic acid (MOPS) buffer aqueous solution (50% CH3CN), BODPAQ displays the highest sensitivity for Zn2+, while in citrate–phosphate buffer, BODPAQ shows no response to Zn2+.
Co-reporter:Chunchang Zhao, Peng Feng, Jian Cao, Yulin Zhang, Xuzhe Wang, Yang Yang, Yanfen Zhang and Jinxin Zhang
Organic & Biomolecular Chemistry 2012 vol. 10(Issue 2) pp:267-272
Publication Date(Web):30 Sep 2011
DOI:10.1039/C1OB06200J
A 6-hydroxyindole-based BODIPY, named BODIPY–OH, with distinct spectroscopic characteristics is reported. Through a systematic study of the spectroscopic characteristics of BODIPY–OH and BODIPY–O− in various solvents containing an organic base, we found that the light-color of the fluorophore can be tuned over a wide range by changing the polarity of solvent/base combinations. The absorption color of the solution can be tuned over a range of 100 nm and the emission color within a wide range from 571 to 681 nm by simply converting the phenol form of BODIPY–OH to the phenolate form. Fluorescence of BODIPY–O− with high quantum yield shows relatively large Stokes shift in solvent/base combinations, which are ascribed to the excited state deprotonation from (BODIPY–OH)* to (BODIPY–O−)*, followed by emission from the ion form.
Co-reporter:Jian Cao, Chunchang Zhao, Peng Feng, Yulin Zhang and Weihong Zhu
RSC Advances 2012 vol. 2(Issue 2) pp:418-420
Publication Date(Web):18 Nov 2011
DOI:10.1039/C1RA00942G
A colorimetric and fluorescent turn-on chemodosimeter for fluoride with high selectivity was developed on the basis of the specific reaction of F− with BODIPY-OSi, displaying a dramatic color change and distinct near-infrared (NIR) fluorescence enhancement at 676 nm.
Co-reporter:Jian Cao, Chunchang Zhao, Weihong Zhu
Tetrahedron Letters 2012 Volume 53(Issue 16) pp:2107-2110
Publication Date(Web):18 April 2012
DOI:10.1016/j.tetlet.2012.02.051
A near-infrared (NIR) fluorescent chemodosimeter for F− was developed on the basis of dicyanomethylene-4H-chromene derivative, with several merits such as a high off/on ratio response, NIR fluorescence, and high selectivity to F−. The F− triggered specific Si–O cleavage of DCPOSi to release DCPO− is responsible for the dramatic color change and distinct NIR fluorescence enhancement at 718 nm.A chemodosimeter shows F−-selective fluorescent response via the specific Si–O cleavage with F−, displaying a dramatic color change and distinct NIR fluorescence enhancement at 718 nm.
Co-reporter:Chunchang Zhao;Peng Feng;Xiaohong Chen;Man-Kit Ng
Macromolecular Chemistry and Physics 2011 Volume 212( Issue 14) pp:1515-1523
Publication Date(Web):
DOI:10.1002/macp.201000728
Co-reporter:Chunchang Zhao, Yu Zhou, Qiuning Lin, Linyong Zhu, Peng Feng, Yulin Zhang, and Jian Cao
The Journal of Physical Chemistry B 2011 Volume 115(Issue 4) pp:642-647
Publication Date(Web):December 17, 2010
DOI:10.1021/jp109845g
Discrimination between chemically related benzenethiols and aliphatic thiols represents a big problem. In this paper, a fluorescent probe, Bodipy-1, containing an indole-based Bodipy as a fluorophore and a 2,4-dinitrobenzenesulfonyl group as a recognition unit was constructed to achieve the selectivity between them. The Bodipy group in the prepared probe was selectively released through aromatic nucleophilic substitution by thiolate anions from benzenethiols, resulting in blue−red switching in the emission spectra in buffer solutions; that is, two new peaks of the phenol/phenolate state of Bodipy-2 at 565 and 629 nm appeared in emission spectra. By varying the pH value from 6.6 to 8.8, the intensity ratio of I565/I629 varies from 2.0 to 0.3 after complete conversion to Bodipy-2, a ca. 7-fold emission ratio change. This ratiometric emission property by varying the pH value makes Bodipy-1 a promising probe to discriminate benzenethiols from aliphatic thiols by careful selection of the reaction pH.
Co-reporter:Chunchang Zhao, Xiaohong Chen, Cen Gao, Man-Kit Ng, Huanjun Ding, Kiwan Park, Yongli Gao
Synthetic Metals 2009 Volume 159(Issue 11) pp:995-1001
Publication Date(Web):June 2009
DOI:10.1016/j.synthmet.2009.01.011
Three new hybrid polycyclic aromatic 4H-indeno[1,2-b]thiophene derivatives (DIT-nT) were readily synthesized and characterized. Ultraviolet photoelectron spectroscopy (UPS) and inverse photoemission spectroscopy (IPES) study shows that the gap energies of these oligothiophene derivatives are dependent on the effective π-conjugation length of the molecules, with decreasing gap energies while the conjugated length is increased. More importantly, the hole injection barrier obtained from UPS and IPES studies decreases significantly at the metal-organic interface as the effective π-conjugation length of the molecules increases. Hence, the hole injection into DIT-2T is expected to be more facile than that into DIT-0T due to the smaller barrier. X-ray diffraction examination revealed that thin films are highly ordered, with the long axes of the molecules nearly perpendicular to the surface. The field-effect transistor (FET) devices based on the three oligomers show good p-type performance with high hole mobilities, and the highest value (0.014 cm2 V−1 s−1) was obtained for the longest oligomer DIT-2T.UPS and IPES study and FET performance show that the new hybrid polycyclic aromatic 4H-indeno[1,2-b]thiophene derivatives (DIT-nT) are good p-type materials. With increasing the π-conjugation length, the hole injection into DIT-2T is more facile than that into DIT-0T, and the highest FET value was obtained for the longest oligomer DIT-2T.
Co-reporter:Li-Li Zhang, Hui-Kun Zhu, Chun-Chang Zhao, Xian-Feng Gu
Chinese Chemical Letters (February 2017) Volume 28(Issue 2) pp:
Publication Date(Web):February 2017
DOI:10.1016/j.cclet.2016.07.008
Most reported fluorescent probes have limitations in practical applications in living systems due to the strong autofluorescence background, construction of probes with near-infrared (NIR) fluorescence emission is an accessible approach for addressing this challenge. We here designed a NIR fluorescent probe for monitoring the endogenous production of H2S in living cells. The designed probe showed significant NIR fluorescence turn-on response to H2S with high selectivity, enabling the sensitive detection H2S. Importantly, the probe could be applied in monitoring the endogenous production of H2S in raw264.7 macrophages. This study showed that fluvastatin can promote the activity of cystathionine γ-lyase (CSE) for generation H2S.A new fluorescent probe was designed for H2S, which showed significant NIR fluorescence turn-on response to H2S with high selectivity. Importantly, the probe has been successfully applied in monitoring the endogenous production of H2S in raw264.7 macrophages upon stimulation with fluvastatin.
Co-reporter:Chunchang Zhao, Peng Feng, Jian Cao, Xuzhe Wang, Yang Yang, Yulin Zhang, Jinxing Zhang and Yanfen Zhang
Organic & Biomolecular Chemistry 2012 - vol. 10(Issue 15) pp:NaN3109-3109
Publication Date(Web):2012/02/07
DOI:10.1039/C2OB06980F
Here, we report a new Cu2+-selective fluorescent turn-on probe BODIPY-EP, in which the 2-pyridinecarboxylic acid is connected to a 6-hydroxyindole-based BODIPY platform through an ester linkage. The ester bond of BODIPY-EP is selectively hydrolyzed by the reaction with Cu2+ under mild and neutral conditions to generate BODIPY-OH, showing strong characteristic fluorescence of BODIPY-OH. The favorable features of BODIPY-EP towards Cu2+ include fast response, large fluorescence enhancement and high selectivity. We further demonstrated that the membrane-permeable probe reacts with intracellular Cu2+ and exhibits bright fluorescence in living cells.
Co-reporter:Feiyi Wang, Li Zhou, Chunchang Zhao, Rui Wang, Qiang Fei, Sihang Luo, Zhiqian Guo, He Tian and Wei-Hong Zhu
Chemical Science (2010-Present) 2015 - vol. 6(Issue 4) pp:NaN2589-2589
Publication Date(Web):2015/02/18
DOI:10.1039/C5SC00216H
In situ monitoring of intracellular thiol activity in cell growth and function is highly desirable. However, the discriminative detection of glutathione (GSH) from cysteine (Cys) and homocystein (Hcy) and from common amino acids still remains a challenge due to the similar reactivity of the thiol groups in these amino acids. Here we report a novel strategy for selectively sensing GSH by a dual-response mechanism. Integrating two independent reaction sites with a disulfide linker and a thioether function into a fluorescent BODIPY-based chemsensor can guarantee the synergetic dual-response in an elegant fashion to address the discrimination of GSH. In the first synergetic reaction process, the thiol group in GSH, Cys and Hcy induces disulfide cleavage and subsequent intramolecular cyclization to release the unmasked phenol-based BODIPY (discriminating thiol amino acids from other amino acids). In the second synergetic process, upon the substitution of the thioether with the nucleophilic thiolate to form a sulfenyl-BODIPY, only the amino groups of Cys and Hcy, but not that of GSH, undergo a further intramolecular displacement to yield an amino-substituted BODIPY. In this way, we make full use of the kinetically favorable cyclic transition state in the intramolecular rearrangement, and enable photophysical distinction between sulfenyl- and amino-substituted BODIPY for allowing the discriminative detection of GSH over Cys and Hcy and thiol-lacking amino acids under physiological conditions. Moreover, this probe exhibits a distinguishable ratiometric fluorescence pattern generated from the orange imaging channel to the red channel, which proves the differentiation of GSH from Cys and Hcy in living cells.
Co-reporter:Chunchang Zhao, Peng Feng, Jian Cao, Yulin Zhang, Xuzhe Wang, Yang Yang, Yanfen Zhang and Jinxin Zhang
Organic & Biomolecular Chemistry 2012 - vol. 10(Issue 2) pp:NaN272-272
Publication Date(Web):2011/09/30
DOI:10.1039/C1OB06200J
A 6-hydroxyindole-based BODIPY, named BODIPY–OH, with distinct spectroscopic characteristics is reported. Through a systematic study of the spectroscopic characteristics of BODIPY–OH and BODIPY–O− in various solvents containing an organic base, we found that the light-color of the fluorophore can be tuned over a wide range by changing the polarity of solvent/base combinations. The absorption color of the solution can be tuned over a range of 100 nm and the emission color within a wide range from 571 to 681 nm by simply converting the phenol form of BODIPY–OH to the phenolate form. Fluorescence of BODIPY–O− with high quantum yield shows relatively large Stokes shift in solvent/base combinations, which are ascribed to the excited state deprotonation from (BODIPY–OH)* to (BODIPY–O−)*, followed by emission from the ion form.
Co-reporter:Qiang Fei, Xianfeng Gu, Yajing Liu, Ben Shi, Hengyan Liu, Ge Xu, Chunbao Li, Ping Shi and Chunchang Zhao
Organic & Biomolecular Chemistry 2017 - vol. 15(Issue 19) pp:NaN4076-4076
Publication Date(Web):2017/04/18
DOI:10.1039/C7OB00383H
Novel BODIPYs undergoing excited state intramolecular proton transfer are reported. The molecules afford NIR emission with a large Stokes shift and possess a free hydroxyl unit that is easy to functionalize, allowing the dyes to be exploited as a valuable scaffold in probe design.
Co-reporter:Chunchang Zhao, Jinxin Zhang, Xuzhe Wang and Yanfen Zhang
Organic & Biomolecular Chemistry 2013 - vol. 11(Issue 2) pp:NaN377-377
Publication Date(Web):2012/11/01
DOI:10.1039/C2OB26791H
In this paper a general procedure for the introduction of pyridone moiety was developed, using a Friedländer reaction, for post-modification of ready-made BODIPY core, from which three pyridone-fused BODIPYs 1, 2 and 3 were generated. This method is complementary to the classical method for obtaining aromatic ring-fused BODIPYs, which begins with the condensation of the corresponding aromatic ring-fused pyrroles. These pyridone-fused BODIPYs are distinctive, possessing favorable photophysical characteristics with strong absorption, high bright orange fluorescence and easy reduction due to the electron-withdrawing effect of the fused pyridone moiety. More important, these BODIPYs bear reactive functions which are applicable in proteins labeling by bioorthogonal chemical reactions.
Co-reporter:Xuzhe Wang, Jian Cao and Chunchang Zhao
Organic & Biomolecular Chemistry 2012 - vol. 10(Issue 24) pp:NaN4691-4691
Publication Date(Web):2012/05/10
DOI:10.1039/C2OB25633A
A novel thiol–sulfoxide reaction based ratiometric probe for benzenethiols was synthesized and evaluated. The probe features a chemospecific reduction over a pH range of 1–10 by benzenethiols with a marked emission color change, enabling the highly selective detection and is promising for applications.
Co-reporter:Chunchang Zhao, Jiancai An, Li Zhou, Qiang Fei, Feiyi Wang, Jie Tan, Ben Shi, Rui Wang, Zhiqian Guo and Wei-Hong Zhu
Chemical Communications 2016 - vol. 52(Issue 10) pp:NaN2078-2078
Publication Date(Web):2015/12/01
DOI:10.1039/C5CC08936K
Two novel probes were designed, sharing the same BODIPY core but differing only by a minimized variation in the recognition site from 4-hydroxyaniline into 4-methoxyaniline. Such a small change in the reaction site could switch the selective detection from peroxynitrite to HOCl. Undoubtedly, the new designed BODIPY core exhibits valuable properties.
Co-reporter:Jian Cao, Chunchang Zhao, Xuzhe Wang, Yanfen Zhang and Weihong Zhu
Chemical Communications 2012 - vol. 48(Issue 79) pp:NaN9899-9899
Publication Date(Web):2012/08/22
DOI:10.1039/C2CC35080G
Based on 6-hydroxyindole BODIPY with a Schiff-base structure, NIR fluorescence with impressively high selectivity is triggered by deprotonation of the phenol group upon binding with Zn2+ due to the chelation-enhanced fluorescence effect, thus realizing a promising application in bioimaging of Zn2+.
Co-reporter:Chunchang Zhao, Yulin Zhang, Peng Feng and Jian Cao
Dalton Transactions 2012 - vol. 41(Issue 3) pp:NaN838-838
Publication Date(Web):2011/11/17
DOI:10.1039/C1DT10797F
A borondipyrromethene-based Zn2+ fluorescent probe BODPAQ was designed and synthesized. The chelators in BODPAQ, 2,2′-dipicolylamine (DPA) and 8-aminoquinoline (AQ), coordinate to Zn2+ in a synergic manner. As a result, BODPAQ displays high Zn2+ selectivity with a dramatic enhanced emission accompanied by a notable hypsochromic shift due to the binary inhibition effect of PET and ICT mechanisms, enabling the detection of Zn2+ by both ratiometric and normal turn-on fluorescence methods in acetonitrile. Interestingly, the sensitivity of BODPAQ towards Zn2+ changes upon varying the compositions of buffer solutions. In 3-morpholinopropanesulfonic acid (MOPS) buffer aqueous solution (50% CH3CN), BODPAQ displays the highest sensitivity for Zn2+, while in citrate–phosphate buffer, BODPAQ shows no response to Zn2+.
Co-reporter:Ben Shi, Xianfeng Gu, Qiang Fei and Chunchang Zhao
Chemical Science (2010-Present) 2017 - vol. 8(Issue 3) pp:NaN2155-2155
Publication Date(Web):2016/11/30
DOI:10.1039/C6SC04703C
H2S is a key chemical mediator that exerts a vital role in diverse physiological and pathological processes. However, in vivo tracking of endogenous H2S generation still remains difficult due to the lack of reliable analytical methods. Herein, we present the first example of activatable photoacoustic probes for real-time imaging of H2S in living mice through the full utilization of the superiority of photoacoustic imaging modality at fine spatial resolution during deep tissue penetration. The designed probe can generate high NIR absorption at 780 nm in the presence of H2S, thus producing a strong photoacoustic signal output in the NIR region. Furthermore, this probe exhibits extremely fast and highly selective responsiveness, good water-solubility and excellent biocompatibility. In light of these outstanding features, this probe realizes the direct photoacoustic trapping of endogenous H2S generation in a HCT116 tumor-bearing mouse model. These preliminary imaging studies show that HCT116 colon tumors exhibit CBS upregulation activity, resulting in an increased rate of H2S generation.
![Borate(2-?)?, difluoro[L-?γ-?glutamyl-?S-?[5-?[[6-?[(ethoxycarbonyl)?oxy]?-?3-?methyl-?2H-?indol-?2-?ylidene-?κN]?phenylmethyl]?-?1H-?pyrrol-?2-?yl-?κN]?-?L-?cysteinylglycinato(3?-?)?]?-?, hydrogen (1:2)?, (T-?4)?-](/data/chemimg/3732500/1782114-45-7.png)
![Borate(2-?)?, difluoro[L-?γ-?glutamyl-?S-?[5-?[[6-?[(ethoxycarbonyl)?oxy]?-?3-?methyl-?2H-?indol-?2-?ylidene-?κN]?phenylmethyl]?-?1H-?pyrrol-?2-?yl-?κN]?-?L-?cysteinylglycinato(3?-?)?]?-?, hydrogen (1:2)?, (T-?4)?-](/data/chemimg/3732500/1782114-45-7_b.png)
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![Boron, [2-?[[5-?[(5-?chloro-?2H-?pyrrol-?2-?ylidene-?κN)?phenylmethyl]?-?1H-?pyrrol-?2-?yl-?κN]?methylene]?propanedinitrilato]?difluoro-?, (T-?4)?-](/data/chemimg/3781100/1801771-53-8.png)
![Boron, [2-?[[5-?[(5-?chloro-?2H-?pyrrol-?2-?ylidene-?κN)?phenylmethyl]?-?1H-?pyrrol-?2-?yl-?κN]?methylene]?propanedinitrilato]?difluoro-?, (T-?4)?-](/data/chemimg/3781100/1801771-53-8_b.png)
![Boron, difluoro[2-?[[5-?[[5-?[(4-?hydroxyphenyl)?amino]?-?2H-?pyrrol-?2-?ylidene-?κN]?phenylmethyl]?-?1H-?pyrrol-?2-?yl-?κN]?methylene]?propanedinitrilato]?-?, (T-?4)?-](/data/chemimg/3732600/1801771-55-0.png)
![Boron, difluoro[2-?[[5-?[[5-?[(4-?hydroxyphenyl)?amino]?-?2H-?pyrrol-?2-?ylidene-?κN]?phenylmethyl]?-?1H-?pyrrol-?2-?yl-?κN]?methylene]?propanedinitrilato]?-?, (T-?4)?-](/data/chemimg/3732600/1801771-55-0_b.png)
![Borate(2-?)?, difluoro[L-?γ-?glutamyl-?S-?[5-?[(6-?methoxy-?3-?methyl-?2H-?indol-?2-?ylidene-?κN)?phenylmethyl]?-?1H-?pyrrol-?2-?yl-?κN]?-?L-?cysteinylglycinato(3?-?)?]?-?, hydrogen (1:2)?, (T-?4)?-](/data/chemimg/3717200/1782114-46-8.png)
![Borate(2-?)?, difluoro[L-?γ-?glutamyl-?S-?[5-?[(6-?methoxy-?3-?methyl-?2H-?indol-?2-?ylidene-?κN)?phenylmethyl]?-?1H-?pyrrol-?2-?yl-?κN]?-?L-?cysteinylglycinato(3?-?)?]?-?, hydrogen (1:2)?, (T-?4)?-](/data/chemimg/3717200/1782114-46-8_b.png)
![Boron(1 )?, [2-?[2-?[2-?chloro-?5-?[(4-?ethyl-?3,?5-?dimethyl-?2H-?pyrrol-?2-?ylidene-?κN)?phenylmethyl]?-?1H-?pyrrol-?3-?yl-?κN]?ethenyl]?-?1-?ethyl-?3,?3-?dimethyl-?3H-?indoliumato]?difluoro-?, bromide (1:1)?, (T-?4)?-](/data/chemimg/3717100/1681062-38-3.png)
![Boron(1 )?, [2-?[2-?[2-?chloro-?5-?[(4-?ethyl-?3,?5-?dimethyl-?2H-?pyrrol-?2-?ylidene-?κN)?phenylmethyl]?-?1H-?pyrrol-?3-?yl-?κN]?ethenyl]?-?1-?ethyl-?3,?3-?dimethyl-?3H-?indoliumato]?difluoro-?, bromide (1:1)?, (T-?4)?-](/data/chemimg/3717100/1681062-38-3_b.png)
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![N,N'-[(4-bromophenyl)methanediyl]bis(3-methylbenzamide)](http://img.cochemist.com/ccimg/6200/6132-45-2.png)
![N,N'-[(4-bromophenyl)methanediyl]bis(3-methylbenzamide)](http://img.cochemist.com/ccimg/6200/6132-45-2_b.png)
