[Selective determination of norepinephrine by a cyclic voltammetric method using poly-proline-modified electrodes].

OBJECTIVE

To establish a new method for determining norepinephrine (NE) in the presence of epinephrine and ascorbic acid using proline-modified glassy carbon electrode (GCE).

METHODS

In phosphate buffer solution (pH 9.0), the poly-proline-modified electrode was prepared by cyclic voltammetry method. The voltammetric behavior of NE on poly(proline) film were analyzed to establish a electrochemical analysis method for determination of NE on the modified electrode.

RESULTS

In PBS (pH 7.0), a couple of redox peaks of NE was observed on the modified electrode. The modified electrode was used to determine NE in a excess of epinephrine (EP) and ascorbic acid (AA) by reduction peak current of cyclic voltammetry. The reduction peak currents were in linear relationship with the NE concentrations within the range of 7.0 x 10(-7) to 1.1 x 10(-4) mol/L, with the detection limit of 6.0x10(-8) mol/L.

CONCLUSION

The modified electrode shows good sensitivity, selectivity, and stability for NE determination, and is well applicable for analysis of injection solution samples.