Thermodynamic and fluorescence emission properties of the Zn(II), Cd(II) and Pb(II) complexes with a fluorescent chelator bearing phenanthroline and naphthalene subunits
作者:Carla Bazzicalupi、Silvia Biagini、Antonio Bianchi、Enrico Faggi、Claudia Giorgi、Paola Gratteri、Fernando Pina、Barbara Valtancoli
DOI:10.1016/j.ica.2011.09.027
日期:2012.2
Abstract The new ligand L consisting of a 1,10-phenanthroline unit bearing in 2,9 positions two triamine branches with terminal naphthalene groups was synthesized and used for protonation and metal ion (Zn(II), Cd(II), Pb(II)) coordination studies. Protonation and metal ion coordination were analyzed by means of potentiometric measurements, affording speciation of the systems and determination of the
摘要合成了由1,10-菲咯啉单元在2,9位带有两个末端萘基的三胺分支组成的新配体L,并用于质子化和金属离子(Zn(II),Cd(II),Pb(II) ))协调研究。质子化和金属离子配位通过电位测量法进行分析,提供系统的形态并确定相关的平衡常数,并通过1 H NMR,UV-Vis和荧光发射光谱法进行分析。L与三种金属离子形成稳定的络合物,对Zn(II)在Pb(II)上的结合具有很高的选择性(pH 8.3左右的选择性系数为42,000),对Cd(II)在Pb(II)上的结合具有很高的选择性)(pH 7时的710的选择性系数。7)和对Zn(II)结合Cd(II)的适度选择性(在pH 9左右的选择性系数约为70)。对于Zn(II)和Cd(II)配合物,观察到由于配位菲咯啉单元与萘基相互作用而在可见光区域发出的激合物,而Pb(II)配合物则被完全淬灭。此类热力学和光化学性质定义了在Pb(II)存在下