Sensitive Determination of Norepinephrine by Capillary Electrophoresis with Indirect Electrochemiluminescence Detection and Its Application to Analysis of Human Urine

A new method for sensitive and rapid indirect electrochemiluminescence(IECL)detection of norepinephrine(NE),synephrine,and isoproterenol with capillary electrophoresis(CE)was developed.IECL detection is based on their quenching effects on Ru(bpy)2+3/tripropylamine(TPA)system.Under the optimum conditions,the detection limits(S/N=3)were 2.6×10-8 mol/L for NE,6.6×10-9 mol/L for synephrine,and 8.4×10-8 mol/L for isoproterenol.The RSD of migration time and peak area were less than 1.3% and 4.4%,respectively.The proposed method was successfully applied to the analysis of NE in the urine samples of 10 healthy people and 10 diabetic nephropathy patients.The results indicate that the content of NE in diabetic nephropathy patients is much higher than that in healthy people.