Liquid chromatographic analysis of alizapride and metoclopramide in human plasma and urine using solid-phase extraction.

A universal rapid, sensitive and selective high-performance liquid chromatographic method with UV detection at 230 nm has been developed for the determination of benzamide drugs in human plasma and urine. Sample pretreatment is carried out using solid-phase extraction columns, resulting in very high extraction recoveries of the compounds investigated (alizapride, metoclopramide, alpiropride, amisulpride). The detector response is linear from 25 to 10,000 ng/ml, and the detection limit is 3 ng/ml for alizapride and 10 ng/ml for metoclopramide. The proposed method is highly suitable for pharmacokinetic studies and for drug monitoring.