A dual-responsive fluorescent turn-on sensor for sensitively detecting and bioimaging of hydrazine and hypochlorite in biofluids, live-cells, and plants

Hydrazine (N2H4) and hypochlorite (ClO-) are extremely harmful to the public health, so it is vitally necessary to detect them in living system. Herein, we developed a new phenthiazine-thiobarbituric acid based dual-analyte responsive fluorescent sensor PT for visually distinguishing and detecting N2H4 and ClO-. PT underwent N2H4/ClO--induced C--C breakage, achieving olive-drab/brilliant green fluorescence lighting-up response to-wards N2H4/ClO- with superb specifity, ultra-sensitivity (detection limit: 15.4 nM for N2H4, 13.7 nM for ClO-), and ultra-fast response (N2H4: <15 s, ClO-: <20 s). The mechanisms for sensing N2H4 and ClO- were investi-gated with support of spectral measurements and DFT investigation. Sensor based paper-strip/silica-gel device was developed for in-field supervision and on-site monitoring of gaseous and aqueous N2H4 and ClO- solution. In addition, the PT was also applied for quantitatively detecting N2H4 and ClO- in soil, food, plants and bio-fluids. Moreover, PT was utilized to visualize exogenous N2H4 and ClO- in living plants and live-cells, demonstrating this sensor utilized as a powerful tool to detect N2H4 and ClO- in biological fields.

Automated summary

Researchers developed a fluorescent sensor PT that can visually distinguish and detect N2H4 and ClO-. It has high sensitivity and fast response time, making it applicable for quantitative detection of N2H4 and ClO- in various samples. The sensor can also visualize the presence of these substances in living plants and cells.