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.