Headspace Solid-Phase Microextraction-Gas Chromatography Method for the Determination of Valproic Acid in Human Serum, and Formulations Using Hollow-Fiber Coated Wire

Abstract

A method was developed for the extraction of valproic acid (VPA) by hollow-fiber coated wire as a lab-made olid-phase microextraction (SPME) fiber and its determination by capillary gas chromatography in human serum and pharmaceutical formulations. In this study, a piece of copper wire coated by polypropylene hollow-fiber membrane Was used as a SPME fiber, and its efficiency for the extraction of VPA from the headspace of samples prior to gas chromatographic analysis was evaluated. The Optimum conditions of microextraction process were selected, and the limit of detection for VPA was found to be 85 mu g L(-1) in solution and 1.7 mg L(-1) in human serum. A low detection limit, a wide linear dynamic range (0.25 - 100 mg L(-1)), good repeatability (RSD%<4 in formulations and RSD%<7 in serum samples) and a hi,,her mechanical durability due to its metallic base are some of the most important advantages of the proposed fiber.