Lo Kenneth Kam-Wing, Lee Terence Kwok-Ming
Department of Biology and Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong, PR China.
Inorg Chem. 2004 Aug 23;43(17):5275-82. doi: 10.1021/ic049750q.
Two luminescent ruthenium(II) polypyridine complexes containing a biotin moiety Ru(bpy)(2)(L1)(2) (1) and Ru(bpy)(2)(L2)(2) (2) (bpy = 2,2'-bipyridine; L1 = 4-(N-((2-biotinamido)ethyl)amido)-4'-methyl-2,2'-bipyridine; L2 = 4-(N-((6-biotinamido)hexyl)amido)-4'-methyl-2,2'-bipyridine) have been synthesized and characterized, and their photophysical and electrochemical properties have been studied. Upon photoexcitation, complexes 1 and 2 display intense and long-lived triplet metal-to-ligand charge-transfer ((3)MLCT) (dpi(Ru) --> pi*(L1 or L2)) emission in fluid solutions at 298 K and in low-temperature glass. We have studied the binding of these ruthenium(II) biotin complexes to avidin by 4'-hydroxyazobenzene-2-carboxylic acid (HABA) assays, luminescence titrations, competitive assays using native biotin, and quenching experiments using methyl viologen. On the basis of the results of these experiments, a homogeneous competitive assay for biotin has been investigated.
合成并表征了两种含有生物素部分的发光钌（II）多吡啶配合物Ru(bpy)(2)(L1)(2)（1）和Ru(bpy)(2)(L2)(2)（2）（bpy = 2,2'-联吡啶；L1 = 4-(N-((2-生物素酰胺基)乙基)酰胺)-4'-甲基-2,2'-联吡啶；L2 = 4-(N-((6-生物素酰胺基)己基)酰胺)-4'-甲基-2,2'-联吡啶），并研究了它们的光物理和电化学性质。光激发后，配合物1和2在298 K的流体溶液和低温玻璃中显示出强烈且长寿命的三重态金属到配体电荷转移（(3)MLCT）（dpi(Ru) --> pi*(L1或L2)）发射。我们通过4'-羟基偶氮苯-2-羧酸（HABA）测定、发光滴定、使用天然生物素的竞争测定以及使用甲基紫精的猝灭实验研究了这些钌（II）生物素配合物与抗生物素蛋白的结合。基于这些实验结果，研究了一种生物素的均相竞争测定法。
