Structural modification of rhodamine-based sensors toward highly selective mercury detection in mixed organic/aqueous media.

摘要: In virtue of the sulfurphilic nature Hg2+, three new sensors RN1, RN2 and RST1 that combine a thiophene group one or two rhodamine choromophores, thiospirolactam chromophore, were designed prepared for selective detection Hg2+ in aqueous media, respectively. These all displayed good brightness fluorescence enhancement following coordination with limits at ppb level. Thus, they have potential distinguishing between safe toxic levels inorganic mercury drinking water. RN1 exhibited chromogenic fluorogenic selectivity over alkali, alkaline earth metals, divalent first-row transition metal ions as well heavy but presence Cu2+ had small significant influence on absorption Hg2+. Compared to introduction sufficient sulfur atoms could increase binding capability towards relative sensor decrease its Hg specific ability. The existence some ions, such Pb2+, Ag+, enhance silent spectra RST1. Spectral evidence X-ray structural investigations complex revealed possible 1:2 complexation behaviour ion Sensor which contains carboxhydrazone arms better selectivity, compared those addition only caused interference under same conditions, demonstrating efficiency robust bis-chelating mode regard