The Simultaneous Assay of Naproxen and Salicylic Acid in Serum Using High Pressure Liquid Chromatography

Abstract

A rapid, sensitive, reverse-phase high pressure liquid chromatographic assay was developed for the simultaneous determination of naproxen and salicylic acid. These compounds are extracted from serum and then separated on a reverse-phase column using an acidified methanol eluent. Utilization of a flow-through fluorescence detector in series with a variable wavelength micro-UV detector enhances the sensitivity of the assay. Application of the assay to therapeutic levels of the drugs in human serum is demonstrated.