A bright water-compatible sugar-rhodamine fluorescence sensor for selective detection of Hg2+ in natural water and living cells

Abstract

By combination of a sugar group and a rhodamine group into one molecule, a bright and specific fluorescent sensor for Hg²⁺ in natural water and living cells was achieved. RG1 features the high quantum efficiency for a Hg²⁺-bound sensor in natural water and sensitivity to environmentally relevant mercury in complex natural samples. The limit of detection of Hg²⁺ of 1 ppb level suggests that RG1 is capable of distinguishing between the safe and toxic levels of inorganic mercury in drinking water. RG1 also establishes excellent Hg²⁺-ion specificity over alkali-, alkaline-earth metals and the first-row transition metals as well as Pb²⁺ and Ag⁺. Investigation on the fluorescence imaging of Hg²⁺ in living cells demonstrates that RG1 might be used for monitoring Hg²⁺ within biological samples.