title: Study of highly efficient bimetallic ruthenium tris-bipyridyl ECL labels for coreactant system.
abstract: A series of bimetallic ruthenium complexes [(bpy)(2)Ru(bpy)(CH(2))(n)(bpy)Ru(bpy)(2)](4+) (1, where bpy is 2,2'-bipyridinyl, n = 3, 5, 8) for the coreactant electrochemiluminescence (ECL) system have been synthesized. Their ECL property at different working electrode has been studied in 0.1 M phosphate buffer by using tripropylamine (TPrA) and 2-(dibutylamino) ethanol (DBAE) as the coreactant. The results demonstrate that the ECL intensity depends largely on the length of the saturated carbon chain linkage: the longer is the carbon chain, the higher is the ECL intensity. A remarkable ECL enhancement (up to about 25 times), in comparison with the commonly used metallic [Ru(bpy)(3)](2+), has been observed from 1c (n = 8) at Pt electrode. With 20 mM TPrA, the log of the ECL intensity increases linearly with the log of complex 1c concentrations over the concentration range of 1.0 x 10(-16) to 1.0 x 10(-6) M at glassy carbon electrode. The detection limit is 1.0 x 10(-16) M at a signal-to-noise ratio of 3. This is the highest ECL detection limit for bimetallic system reported until now. The study provides a general methodology to further improve and tune the ECL efficiency by using multimetallic ruthenium complexes.
authors.affiliation: State Key Laboratory of Fine Chemicals, Dalian University of Technology, No. 158-40, Zhongshanlu, Xigang District 116012, Dalian, China. shiguo@dlut.edu.cn
authors.forename: Shiguo
authors.initials: S
authors.lastname: Sun
authors.forename: Yang
authors.initials: Y
authors.lastname: Yang
authors.forename: Fengyu
authors.initials: F
authors.lastname: Liu
authors.forename: Yi
authors.initials: Y
authors.lastname: Pang
authors.forename: Jiangli
authors.initials: J
authors.lastname: Fan
authors.forename: Licheng
authors.initials: L
authors.lastname: Sun
authors.forename: Xiaojun
authors.initials: X
authors.lastname: Peng
mesh_terms: D002082:Butylamines / Q000737:chemistry*; D004563:Electrochemistry; D004566:Electrodes; D000431:Ethanol / Q000031:analogs & derivatives* / Q000737:chemistry; D049449:Luminescence; D009942:Organometallic Compounds / Q000032:analysis* / Q000138:chemical synthesis; D010984:Platinum / Q000737:chemistry; D011437:Propylamines / Q000737:chemistry*; D011725:Pyridines / Q000737:chemistry*; D012428:Ruthenium / Q000737:chemistry*
chemical_list: D002082:Butylamines; D009942:Organometallic Compounds; D011437:Propylamines; D011725:Pyridines; C096226:tripropylamine; C517744:2-(dibutylamino)ethanol; D000431:Ethanol; D010984:Platinum; D012428:Ruthenium