将罗丹明B(RhB)及罗丹明6G(Rh6G)应用于水中Hg2+的荧光猝灭法测定.在KI存在时,Hg2+可与罗丹明类小分子及KI形成多元离子缔合物,故在水中可直接利用体系的荧光发射峰强度测定Hg2+.通过比较两种罗丹明类荧光探针的检测特性发现,两种罗丹明类小分子都是荧光检测特性较好的猝灭型探针,其中罗丹明6G由于其分子结构稳定性大,故灵敏性、线性范围和选择性均高于罗丹明B. Rhodamine B (RhB) and Rhodamine 6G (Rh6G) were applied to the fluorescence quenching of Hg2 + in water, Hg2 + could form multiple ion association with small molecules of rhodamine and KI in the presence of KI, Hg2 + can be directly used to determine the fluorescence emission peak intensity of the system. By comparing the detection characteristics of two rhodamine fluorescent probes, it is found that both rhodamine small molecules are quenching probes with better fluorescence detection properties. Among them, Ming 6G because of its molecular structure stability, so the sensitivity, linear range and selectivity are higher than rhodamine B.