Ultrasensitive and selective detection of Hg2+ using fluorescent phycocyanin in an aqueous system

Construction of fluorescent logic gates for the detection of mercury(II) and ciprofloxacin based on phycocyanin

Chemical pollutants such as heavy metals and antibiotics in the environment pose a huge threat to humans and animals. Our studies have demonstrated that the fluorescence of phycocyanin showed quenching responses towards both mercury (Hg2+) and ciprofloxacin (CIP), which acted in accordance with the "OR" molecular logic gate. In order to discriminate Hg2+ and CIP in application scenarios, cysteine (Cys) was utilized to design another "INHIBIT" logic gate, in which Hg2+ and Cys were the two inputs. Thus, an intelligent biosensor with dual-target identification capacity was successfully developed by using a fluorescent natural protein in an ingenious logic gate system.