Bithiophene-benzothiazole fluorescent sensor for detecting hypochlorite in water, bio-fluids and bioimaging in living cells, plants and zebrafish

Rationally designed and effectively synthesized D-pi-A chemosensor DTA containing bithiophene fluorophore by using bithiophene aldehyde and benzothiazole salt and serves as highly specific chemosensor for colorimetric/ fluorimetric turn-on detection of hypochlorite (ClO-) in-100 % aqueous media. DTA has obvious advantages of high specificity, short response time (8 s), broad pH working scope, ultra-sensitivity with low detection limit (5.3 nM), good bio-compatibility and permeability. The responding mechanism of DTA toward ClO- was investigated by 1H NMR, FTIR, HRMS, optical spectra and DFT calculations. Interestingly, DTA coated silica-gel, cotton buds, and filter-paper test strips were developed for qualitative and quantitative visual detection of ClO- in real-time. Notably, DTA was utilized to quantitatively detect ClO- in real-water and bio-fluids. Moreover, DTA was also applied to bioimage ClO- in live-cells, zebrafish and plant kingdoms, highlighting its broad application poten-tials. The simple structure and versatility of the DTA provides a convenient approach for developing multi-functional sensors and expanding its broader application fields.