A fluorescent turn-on probe based on coumarin-thiourea conjugate for Hg2+detection in a wide pH range

A fluorescent probe (probe C) based on coumarin-thiourea conjugate was developed for selective detection of Hg2+. Addition of Hg2+to probe C induced obvious enhancement of the fluorescence intensity. Probe C exhibited good selectivity toward Hg2+and good anti-interference performance over other common competitive metal ions including Na+, K+, Ag+, Cu2+, Zn2+, Co2+, Ni2+, Mn2+, Mg2+, Fe2+, Fe3+, Ca2+and Al3+. The detection limit of probe C for Hg2+was calculated to be 0.44 nM. It was capable of detecting Hg2+ion in a wide pH range of 1.0–10.0.