Sensitive hydrazine detection and quantification with a fluorescent benzothiadiazole sensor: selective lipid droplets and in vivo imaging

In this work, we describe the design, synthesis, characterization, photophysical evaluation, DFT calculations, and application of two novel fluorescent benzothiadiazole (BTD) sensors for hydrazine detection and quantification at the cellular and multicellular (in vivo) levels. The two probes were fully characterized, and their photophysical properties were evaluated. We tested the designed fluorogenic dye (named BTD-CHO) as a selective sensor for the rapid, sensitive, and selective detection of hydrazine. When treated with N2H4, the probe affords a new derivative named BTD-HZN, releasing water as the only byproduct. BTD-CHO exhibited a preference for lipid droplets (LDs) and accumulated inside these organelles. Hydrazine detection in LDs could be carried out by the in situ formation of BTD-HZN inside live cells. We efficiently visualized the lipids of a challenging cellular model, microalgae (Chlorella sorokiniana), using these sensors. In vivo experiments indicated rapid and efficient detection of the analyte using C. elegans and zebrafish (Danio rerio) as the multicellular models.

Automated summary

In this study, we developed two novel fluorescent benzothiadiazole (BTD) sensors for the detection and quantification of hydrazine at cellular and multicellular levels. The probes were fully characterized, and their photophysical properties were evaluated. The designed fluorogenic dye, BTD-CHO, showed selective detection of hydrazine and generated BTD-HZN as the only byproduct. The sensors successfully visualized lipids in microalgae and efficiently detected hydrazine in C. elegans and zebrafish.