Bingxiang Wang

N-doped carbon dots synthesized by rapid microwave irradiation as highly fluorescent probes for Pb2+ detection

In this study, N-doped carbon dots (NCDs) could be prepared by using glycerol as the carbon source and ethylenediamine as a nitrogen doped molecule through a one-step microwave irradiation method. The resulting NCD probes could exhibit linear fluorescence response to Pb2+ at a detection limit as low as 15.0 nM, which could be applied for trace levels of direct pb2+ recognition.

Microwave-assisted preparation of N-doped carbon dots as a biosensor for electrochemical dopamine detection

A new N-doped carbon dots (NCDs) could be prepared by using the microwave-assisted technique within 10 min without the need for any solvent or catalyst. The NCDs exhibited a highly sensitive electrochemical response toward dopamine (DA) in Phosphate Buffered Saline (PBS) (pH=6.5). The detection limit of DA was calculated by differential pulse voltammetry (DPV) as low as 1.2×10(-9) mol/L with a linear dynamic range of 5.0×10(-8) to 8.0×10(-6) mol/L. These results suggested that this new NCDs could be effectively used for the direct and rapid detection of trace levels of DA in human serum and urine samples.

A novel benzothiazole-based fluorescent probe for cysteine detection and its application on test paper and in living cells

A novel simple and readily synthesized turn-on fluorescent probe 4-(benzo[d]thiazol-2-yl)-1,3-phenylene bis(2-chloroacetate) (BPBC) for cysteine (Cys) was reported. This probe was designed based on an excited-state intramolecular proton transfer (ESIPT) dye: benzothiazole, and two chloroacetate groups present in benzothiazole as the reaction sites for Cys. It shows high selectivity and sensitivity for Cys over other amino acids including the similar structured homocysteine (Hcy) and glutathione (GSH). In addition, probe BPBC was successfully applied to bioimage intracellular Cys in living cells with low cytotoxicity. More importantly, a paper test strip system was developed with probe BPBC for Cys detection conveniently.

A novel near-infrared fluorescent probe for highly selective detection of cysteine and its application in living cells

A novel red-emitting fluorescent probe (DDNA) for cysteine has been rationally designed and synthesized, which exhibited a low limit of detection to Cys (0.26 μM) as well as a favorable large stokes shift (λEm-λEx = 128 nm). This novel fluorophore (HDM), which features a large π-conjugation system and typical intramolecular charge transfer (ICT) process, has a long emission wavelength at 631 nm. Besides that, as a turn-on fluorescent probe, it shows high selectivity and sensitivity for Cys over other metal ions and amino acids including the similar structured homocysteine (Hcy) and glutathione (GSH). Finally, the probe DDNA was successfully applied to bioimage intracellular Cys in Hela cells with low cytotoxicity.

A novel near-infrared and naked-eyes turn on fluorescent probe for detection of biothiols with a large Stokes shift and its application in living cells

A novel turn-on fluorescent probe (DDND) for highly selective detection of biothiols over other amino acids was synthesized and investigated in this work, which used the 2,4-dinitrobenzenesulfonyl (DNBS) group as a fluorescent quencher. The novel fluorophore (HDM) features a large π-conjugation system and a typical intramolecular charge transfer (ICT) process and has a long emission wavelength at 623 nm as well as a large Stokes shift (λem − λex = 131 nm). Besides that, this red-emitting probe exhibited good linearity ranges with a low detection limit of 0.23 μM for Cys, 0.34 μM for Hcy and 0.41 μM for GSH respectively. Upon titration of thiols, the color of the solution changed from yellow to dark red, which means it can be detected by naked eyes. Finally, probe DDND was successfully applied to bioimage intracellular Cys in HeLa cells with low cytotoxicity.