Benzothiazole Derivatives As Fluorescent Probes For Detection Of Toxic Species

Fluorescent probes have been widely applicated in detection of some pollutants and biological species.And when combined with fluorescence imaging,fluorescent probes could be used for real-time imaging in vivo and vitro.Recently,fields of fluorescent probes have got significant developments.However,there are still some problems that need to be solved.This paper revolves around detection of three kinds of analytes associated with human health and environment and then fluorescent probes with excellent properties have been synthetized and studied.Firstly,synthesizing fluorescent probes for the detection of Hg²⁺,a toxic metal ion harmful for human health.A ratiometric fluorescent probes CTBT?2-?2?-hydroxy-4?-phenyloxythioformyloxy?phenylbenzothiazole?for Hg²⁺detection exhibits feature of high sensitivity?detection limit=8.1 nM?,quick response,high selectivity over other common metal ions,and capability of working a wide pH range.Moreover,this probe is able to detect Hg²⁺in real samples.Another fluorescent probes CTMC?4-methyl-7-phenyloxy thioformyloxycoumarin?not only displays some properties that include high sensitivity,quick response,high selectivity and so on but have prominent water-solubility—it can work in water containing 0.1%DMSO that approaches pure water.Secondly,two kinds of fluorescent probes,NDEB?2-?4?-diethylamino-2?-?2?,4?-dinitrophenoxy??phenylbenzothiazole?and NHBT?2-di?2?,4?-dinitrophenoxy?phenyl benzothiazole?are designed and synthesized for detection of H₂S,which is one of the reactive sulfur species and a gasotransmitter.NDEB exhibits high selectivity and sensitivity.More importantly,response time for H₂S is very short.Also,NHBT exhibits high selectivity and sensitivity.But NHBT responses for H₂S more slowly than NDEB.The two fluorescent probes all displays excellent properties when detecting H₂S in solution.Finally,given that peroxynitrite?ONOO??is profoundly associated with health and diseases,a new fluorescent probe ABT?4-?2?-benzothiazolyl-5?-methoxy?phenoxymethyl-1-phenylboronic acid pinacol ester?was designed and synthesized for detection of ONOO?.ABT manifested not only ratiometric fluorescence signals simultaneously in response to concentrations of ONOO??within 10s?,but high selectivity and sensitivity towards ONOO?over other physiological relevant species?detection limit=26.3 nM?.Moreover,ABT worked in a broad pH range with biological relevance.