Article

Photoluminescent and electrochemiluminescent dual-signaling probe for bio-thiols based on a ruthenium(II) complex.

State Key Laboratory of Fine Chemicals, School of Chemistry, Dalian University of Technology, Dalian 116024, PR China.
Analytica chimica acta (Impact Factor: 4.31). 08/2012; 740:80-7. DOI: 10.1016/j.aca.2012.06.028
Source: PubMed

ABSTRACT Photoluminescence (PL) and electrochemiluminescence (ECL) detection techniques are highly sensitive and widely used methods for clinical diagnostics and analytical biotechnology. In this work, a unique ruthenium(II) complex, [Ru(bpy)(2)(DNBSO-bpy)](PF(6))(2) (bpy: 2,2'-bipyridine; DNBSO-bpy: 2,4-dinitrobenzenesulfonate of 4-(4-hydroxyphenyl)-2,2'-bipyridine), has been designed and synthesized as a highly sensitive and selective PL and ECL dual-signaling probe for the recognition and detection of bio-thiols in aqueous media. As a thiol-responsive probe, the complex can specifically and rapidly react with bio-thiols in aqueous solutions to yield a bipyridine-Ru(II) complex derivative, [Ru(bpy)(2)(HP-bpy)](2+) (HP-bpy: 4-(4-hydroxyphenyl)-2,2'-bipyridine), accompanied by the remarkable PL and ECL enhancements. The complex was used as a probe for the PL and ECL detections of cysteine (Cys) and glutathione (GSH) in aqueous solutions. The dose-dependent PL and ECL enhancements showed good linear relationships against the Cys/GSH concentrations with the detection limits at nano-molar concentration level. Moreover, the complex-loaded HeLa cells were prepared for PL imaging of the endogenous intracellular thiols. The results demonstrated the practical utility of the complex as a cell-membrane permeable probe for PL imaging detection of bio-thiols in living cells.

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