A novel electrochemiluminescence sensor based on bis(2,2'-bipyridine)-5-amino-1,10-phenanthroline ruthenium(II) covalently combined with graphite oxide.

This communication reports a novel electrochemiluminescence (ECL) sensor based on covalently linking bis(2,2'-bipyridine)-5-amino-1,10-phenanthroline ruthenium(II) (Ru(II)-NH2) with graphite oxide (GO) on a glassy carbon electrode. 1-ethyl-3-(3-dimethylaminopropyl)-carbodiimide hydrochloride and N-hydroxy-succinimide were applied to activate the carboxyl groups on the GO surface and catalyze the formation of amido link between Ru(II)-NH2 and carboxyl groups on GO. The composite film was characterized using atomic force microscopy, transmission electron microscopy and Fourier transform infrared absorption spectroscopy. Based on ECL experimental results, the composite film modified electrode displayed high electrochemical activity towards the oxidation of 2-(dibutylamino) ethanol (DBAE). Under optimized conditions, the linear response of ECL intensity to DBAE concentration was valid in the range 6.0×10(-7)-2.0×10(-4) mol L(-1) (r2=0.9948) with a detection limit (S/N=3) of 5.0×10(-8) mol L(-1). Furthermore, the ECL sensor presented good characteristics in terms of stability and reproducibility, promising the development of ECL sensors for biologically important compounds.