New fluorescent probes for mercury(II) with simple structure

Based on the protection reaction between ethanethiol and aldehyde, a novel fluorescent probe (2) for Hg2+ ions, with the simplest structure reported so far, was designed, which displayed high sensitivity and selectivity towards Hg2+ and Ag+ over other metal ions with detectable fluorescent signals, due to distinct deprotection reaction of dithioacetal. Compound 2 was further utilized to construct the chemical reaction-based conjugated polymer probes (P2 and P4) for Hg2+ ions. More importantly, the effect of the molecular weight of conjugated polymers on the sensitivity of the probes towards Hg2+ ions was carefully studied.