Analytical Sciences

Abstract − Analytical Sciences, 25(7), 875 (2009).

Headspace Solid-Phase Microextraction-Gas Chromatography Method for the Determination of Valproic Acid in Human Serum, and Formulations Using Hollow-Fiber Coated Wire
Mir Ali FARAJZADEH,*1 Khalil FARHADI,*2 Amir A. MATIN,*2,*3 Paria HASHEMI,*2 and Abolghasem JOUYBAN*4
*1 Department of Analytical Chemistry, Faculty of Chemistry, University of Tabriz, Tabriz, Iran
*2 Department of Chemistry, Faculty of Science, Urmia University, Urmia, Iran
*3 Research Department of Chromatography, Iranian Academic Center for Education, Culture & Research (ACECR), Urmia, Iran
*4 School of Pharmacy & Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz 51664, Iran
A method was developed for the extraction of valproic acid (VPA) by hollow-fiber coated wire as a lab-made solid-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 μg 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 higher mechanical durability due to its metallic base are some of the most important advantages of the proposed fiber.