Abstract:
Fluorescence and colorimetric sensors based on rhodamine (monoRh6G, diRh6G and RhB-Silica) had been successfully synthesized for detection of Hg2+ and their sensing behaviors toward metal ions were investigated by fluorescence spectroscopy and UV/Vis spectroscopy. The sensors exhibited a selective OFF-ON fluorescence enhancement sensing toward Hg2+ and provided high selectivity to Hg2+ in the presence of other metal ions, such as Ag+, Cu2+, Ba2+, Li+, Pb2+, Ca2+, Cd2+, Co2+, Fe2+, Mn2+, Na+, Ni2+, K+ and Zn2+. Importantly, the color of the sensors changed from colorless to pink in the presence of Hg2+, which was noticeable for naked eye detection. Especially, RhB-Silica was developed for an on-site preliminary screening of Hg2+ which consisted of rhodamine B hydrazide attached to silica gel as a solid support. The developed sensors are practical for easily handle and screening of Hg2+ in aqueous samples in the environments.