The fluorescent probe based on methyltetrahydroxanthylium skeleton for the detection of hydrazine

Two probes based on tetrahydroxanthylium unit (probe 1a) and methyltetrahydroxanthylium unit (probe 1b) were designed and synthesized for the detection of hydrazine. Probes 1a-b exhibited turn-on red emission signal and high selectivity toward NH2NH2. The response time of probe 1a to NH2NH2 was more than 60 min, while that of probe 1b was less than 30 min. The detection limits of probes 1a-b were calculated as 210 nM and 110 nM respectively. What's more, the tolerance experiments showed that methyltetrahydroxanthylium unit possessed higher tolerance toward nucleophiles. Moreover, cells imaging experiments demonstrated that probe lb could detect exogenous NH2NH2 in living HeLa cells.