An organopalladium chromogenic chemodosimeter for the selective naked-eye detection of Hg2+ and MeHg+ in water-ethanol 1 : 1 mixture

An organopalladium chemical dosimeter of Hg2+ that methylates Hg2+, undergoing a colour change in 1 : 1 ethanol-water with submicromolar sensitivity, gives rise to an aqua-palladium complex that is methylated by MeHg+ in the presence of a dithiol compound, undergoing another colour change, thus making the system suitable for the naked-eye detection of Hg2+ and MeHg+, two environmentally important species of Hg2+.