Electrochemical-Ion-Chromatographic Determination of Ephedrine Hydrochloride Using Carbon Nanotube Modified Electrode Amperometric Detector

In the present method,ephedrine hydrochloride was separated by anion-exchange,a mixed solution of sodium carbonate and methanol was used as eluant,and direct current amperometric detection with carbon nanotube modified glassy carbon electrode at 0.8 V was adopted in the determination.It was found that by using the modified electrode,detection limit of the method was lowered about 10 times as compared with the method by using un-modified electrode.Value of DL with un-modified electrode was 2.4 μg·L-1,and that with modified electrode was 0.2 μg·L-1.Recovery of the method with modified electrode was found to be 103.6%.