title: Tris(2,2'-bipyridyl)ruthenium(II) electrochemiluminescence sensor based on carbon nanotube/organically modified silicate films.
abstract: In this paper, a novel electrochemiluminescence (ECL) sensor was constructed to determine herring sperm (HS) double-stranded (ds) DNA. Tetramethoxysilane and dimethyldimethoxysilane were selected as co-precursors to form an organically modified silicate (ORMOSIL) film for the immobilization of multiwall carbon nanotubes (MWNTs) wrapped by poly(p-styrenesulfonate) (PSS), and then Tris(2,2'-bipyridyl)ruthenium(II) (Ru(bpy)3(2+)) was successfully immobilized on a glassy carbon electrode via ion-association. PSS was employed to increase the conductivity of the ORMOSIL film and disperse the cut MWNTs, which were cut and shortened in a mixture of concentrated sulfuric and nitric acids, in the film. It was found that MWNTs could adsorb Ru(bpy)3(2+) and acted as conducting pathways to connect Ru(bpy)3(2+) sites to the electrode. MWNTs also played a key role as materials for the mechanical and thermal properties. The ECL performance of this modified electrode was evaluated in a flow injection analysis (FIA) system, and the detection limit (S/N=3) for HS ds-DNA was 2.0x10(-7) g mL(-1) with a linear range from 1.34x10(-6) to 6.67x10(-4) gm L(-1) (R2=0.9876). In addition, the ECL sensor presented excellent characteristics in terms of stability, reproducibility and application life.
authors.affiliation: Department of Chemistry and Key Laboratory of Analytical Sciences of the Ministry of Education, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Tao
authors.forename: Zhi-Jie
authors.initials: ZJ
authors.lastname: Lin
authors.forename: Xiao-Mei
authors.initials: XM
authors.lastname: Chen
authors.forename: Xi
authors.initials: X
authors.lastname: Chen
authors.forename: Xiao-Ru
authors.initials: XR
authors.lastname: Wang