A highly selective pyrene based fluorescent sensor toward Hg2+ detection

A new pyrene-containing fluorescent sensor has been synthesized from 2,3,3-trimethylindolenine. Spectroscopic and photophysical properties of sensor are presented. The large change in fluorescence intensity (I/I0 = 0.13) at 381 nm and affinity to Hg2+ over other cations such as K+, Na+, Ca2+, Mg2+, Pb2+, and Cu2+ make this compound a useful chemosensor for Hg2+ detection in hydrophilic media. The sensor (6.0 × 10−6 M) displays significant fluorescence quenching upon addition of Hg2+ in pH 7.4 HEPES buffer without excimer formation. Job’s plot analysis shows the binding stoichiometry to be 2:1 (host/guest).