DETERMINATION OF OPIATES IN URINE BY CAPILLARY ELECTROPHORESIS

A method for the separation of a mixture of opiates comprising pholcod ine, 6-monoacetylmorphine, morphine, heroin, codeine and dihydrocodein e by capillary electrophoresis using a running buffer of 100 mM disodi um hydrogenphosphate at pH 6 is described. The characteristics of an a nalytical method based on this separation for the determination of the se drugs following extraction from urine and using levallorphan as int ernal standard are reported. Detection limits in the region of 10 ng c m(-3) are achieved when using electrokinetic injection. A comparison i s made of the sensitivity and reproducibility of electrokinetic and hy drodynamic injection for these drugs. Data are presented to show the r esults obtained when the proposed method is applied to urine spiked wi th all the above opiates and also to urine from a subject following co nsumption of dihydrocodeine and pholcodine. The concentrations found a re compared with those obtained by LC.