谷氨酸桥连芘基、大环多胺荧光探针对Cu2+离子的选择性识别初探

new cyclen (1, 4, 7, 10-tetrazacyclodo decane) derivative 4 was prepared. The modified cyclen moiety that appended a glutamic acid side chain showed a better Cu2+ fluorescence selectivity and binding ability than other similar cyclen derivatives. The association constant (Kassoc) of 4 for Cu2+ is 2×106 M-1. Fluorescence quench experiments were carried out to compare the fluorescence selectivity ability of different metal ions. The fluorescence of the ligand could be sensitively quenched by 1 eq. of Cu2+. By adding 100 eq. of metal ions in methanol aqueous solution of 4, the selectivity of Cu2+ is much higher than other metal ions except Hg2+. The particular selectivity, efficient fluorescence quenching behavior of 4 to Cu2+ ion led us to think that 4 could be used as a new chemosensor for the analysis and measurement of Cu2+ ion in aqueous solution.