[Determination of 17-hydroxycorticosteroid by capillary zone electrophoresis]

To detect and dissociate 17-hydroxycorticosteroids(17-OHCS) in urine by using high performance capillary zone electrophoresis(CZE) so as to solve the problem that phenolic compounds interfere with the determination of urine 17-OHCS by chromatographic-spectrophotometry.

Pigments were absorbed from samples by activated kaolin in which the internal standard was theophyline. Urine 17-OHCS was absorbed by neutral styrene-divinylbenzene resin. Thus pigments and phenolic compounds were separated roughly. Then 17-OHCS was washed down by alcohol and separated and detected by capillary zone electrophoresis.

Urinary 17-OHCS was separated successfully. Urinary 17-OHCS had a good linearity in the range of 2-50 mg.L-1 (r = 0.994). The average recovery rate was 96.17%. The relative standard deviation was less than 5%. The consistence detection limit was 0.3 mg.L-1.

Compared with chromatographic-spectrophotometry, the high performance capillary electrophoresis has much less interference and is more simple, rapid, and accurate.