Determination of noradrenaline and dopamine in pharmaceutical injection samples by inhibition flow injection electrochemiluminescence of ruthenium complexes.
Two maximal potential-resolved flow injection-electrochemiluminescent (FI-ECL) peaks were observed for Ru(bpy)(3)(2+)/TPrA system at 0.90 and 1.05 V, and for Ru(phen)(3)(2+)/TPrA at 1.01 and 1.25 V (vs. Ag/AgCl) in pH 8.0 phosphate buffer solutions. Sensitive ECL inhibition effects were observed in the presence of noradrenaline and dopamine for both of these systems. Therefore, an FI-ECL inhibition method for determination of noradrenaline and dopamine has been developed. Under optimal conditions, linear responses between logarithm of ECL intensity changes and logarithm of sample concentration were found for noradrenaline in the linear range (LR) of 4x10(-8)-1x10(-5) moll(-1) with theoretical detection limit (DL) of 2.5x10(-8) moll(-1) for Ru(bpy)(3)(2+)/TPrA system, and in LR of 2x10(-8)-2x10(-5) moll(-1) with DL of 7.1x10(-9) moll(-1) for Ru(phen)(3)(2+)/TPrA system; and for dopamine in LR of 8x10(-8)-2x10(-5) moll(-1) with DL of 5.2x10(-8) moll(-1) for Ru(bpy)(3)(2+)/TPrA system, in LR of 4x10(-8)-2x10(-5) moll(-1) with DL of 1.5x10(-8) moll(-1) for Ru(phen)(3)(2+)/TPrA system. It was applied for determination of commercial pharmaceutical injection samples with satisfied results. The mechanism of the inhibition effects was proposed in the preliminary way.
Li
Feng
F
Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China.
Pang
Yong-Qiang
YQ
Lin
Xiang-Qin
XQ
Cui
Hua
H