DETERMINATION OF EPININE IN HUMAN URINE BY HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHY COUPLED WITH ELECTROCHEMICAL DETECTION USING CARBON-FIBERMICROELECTRODES

Epinine was detected with a simple and disposable carbon fiber flow el ectrode after being separated by high-performance liquid chromatograph y (HPLC). An alumina adsorption procedure was used for the extraction of epinine from urine samples. The extraction recoveries at 1, 3, and 6 mu g/mL epinine concentration levels were 66.9 +/- 3.7, 65.6 +/- 3.3 , and 67.0 +/- 3.4%, respectively (n = 5). Linear responses to epinine in urine were obtained over the range of 0 to 10 mu g/mL. The detecti on limit (signal-to-noise ratio = 5/1) for epinine in urine was 15 ng/ mL.