Validated high-performance liquid chromatographic assay for the determination of promazine in human plasma. Application to pharmacokinetic studies.

A high-performance liquid chromatographic method for the determination of promazine in human plasma is described. The assay involves a single-step liquid-liquid extraction using pentane-2-propanol (98:2, v/v). The analyte of interest and the internal standard chlorpromazine were separated on a Spherisorb CN column using a mobile phase of acetonitrile-50 mM ammonium acetate (9:1, v/v). Electrochemical detection was achieved using an applied potential of +750 mV. The assay was validated according to international requirements prior to application to a pharmacokinetic study and was found to be specific, accurate and precise with a linear range of 0.25-25 ng ml(-1).