2-(Dibutylamino)ethyl acrylate as a highly efficient co-reactant of Ru(bpy)32+ electrochemiluminescence for selective detection of cysteine

A highly efficient co-reactant of Ru(bpy) 3 2+ electrochemiluminescence (ECL), 2-(dibutylamino)ethyl acrylate(DBAEA), was successfully synthesized by a straightforward one-step reaction between dibutylaminoethanol and acrylyl chloride. On account of the interaction between the olefin group of DBAEA and Pt electrode, the ECL intensity utilizing DBAEA as the co-reactant was increased dramatically, nearly as 10 times and 17 times as conventional co-reactants dibutyaminoethanol and tripropylamine . Since cysteine can remove the acrylate group of DBAEA specifically through conjugated addition/cyclization reaction, the ECL intensity of Ru(bpy) 3 2+ /DBAEA was declined selectively. Therefore, cysteine was detected through this novel ECL system with high selectivity towards other amino acids . The linear range was between 10 μM and 200 μM with a limit of detection of 1.15 μM. The cysteine in Dulbecco’s Modified Eagle Medium (DMEM) was detected and satisfying recovery was obtained.