Design,Synthesis And Detection Properties Of Fluorescent Probes Based On Anthraquinone And Benzothiazole

Organic fluorescent probes stand out from many analytical methods because of its low cost,simple operation,high sensitivity and fast response and have become a research hotspot.Until now,A large number of fluorescent probes have been developed for detection of different metal cations.However,there are relatively few reports on the detection of anions and small biomolecules and need to be further improved.1,4-dihydroxyindole contains two hydroxyl groups and benzothiazole has simple synthesis,large stokes shift,good light stability and can form excited state intramolecular charge transfer,which are the right precursor for designing new fluorescent probes.In this article,three reactive fluorescent probes were designed and synthesized based on 1,4-dihydroxyanthraquinone and benzothiazole derivatives as the fluorophores,and studied detection performance and recognition mechanism of probe towards fluoride,hydrazine hydrate,bisulfite and biothiol.Its main contents are as follows:1.Design,synthesis and application of fluoride ion fluorescent probe based on anthraquinone derivatives.Based on strong molecular structure rigidity and luminescence properties of 1,4-dihydroxyindole,design and synthesis of a fluoride ion fluorescent probe with 1,4-dihydroxyindole as fluorophore and tert-Butyldimethylchlorosilane as a recognition group,Then,by the characteristics of the the silicon affinity of fluoride ions,the Si-O bond in the probe molecule is induced to break,and the fluorescent signal is released.Through the study of its detection performance,it was found that the probe has good selectivity and sensitivity,and Fcan be detected in a wide range of p H(3-12).The detection limit was calculated to be 0.32 μM.In addition,the probe can be also be applied to the detection of F-in actual water samples.2.Design and synthesis of hydrazine hydrate and bisulfite double-responsive fluorescent probe based on benzothiazole derivatives.Preparation of fluorescent probes with differential dual detection capabilities for hydrazine hydrate and bisulfite though benzothiazole as a fluorophore and ethyl cyanoacetate as the recognition group.The probe achieves qualitative and quantitative detection of both analytes in DMSO:PBS(1:4,v:v)buffer solution.when hydrazine hydrate is detected,a reduction-condensation reaction is occurred,the aldehyde structure is formed and a yellow fluorescent signal is released.The fluorescence intensity is enhanced by 5.6 times(500 nm)and the detection limit is 3.6 μM.When HSO3-was detected,an addition is occurred,a new product is generated,blue fluorescence is emitted,and the fluorescence intensity is enhanced by 7.5 times(458 nm)with a detection limit of 0.52 μM.The probe has good sangelectivity,sensitivity and fast response,especially in response to HSO3-within 3 min.In addition,it is also possible to give fluorescent signals of different colors to the detected substances,and to identify and distinguish N2H4·H2O(yellow-green light)and HSO3-(blue light)by the naked eye..This provides an effective way for the design of multifunctional fluorescent probes.3.Design and synthesis of biothiol fluorescent probe based on benzothiazole derivatives.A fluorescent probe for detecting biothiol(GSH/Hcy/Cys)was designed and synthesized based on benzothiazole as a fluorophore and nitromethane as a recognition group.The probe uses a nitroolefin in the molecule as a recognition site to undergo an electrophilic addition reaction with a thiol group of a biothiol to produce a new product,and the fluorescence signal is significantly enhanced.The probe has good selectivity,sensitivity and naked eye recognition ability,the biothiol(GSH/Hcy/Cys)could be detected in 20 % organic solvent,and the detection limit was calculated to be 0.33 μM,0.70 μM and 0.87 μM.and is expected to be further applied in biosensing.