ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Square-wave adsorptive stripping voltammetric determination of an antihistamine drug astemizole

Ahmad H. Alghamdi

Department of Chemistry, College of Science, King Saud University, P.O Box 2455, 11451 Riyadh, Saudi Arabia

E-mail: ahalgamdy@hotmail.com

Received: 1 July 2007  Revised: 19 November 2007  Accepted: 20 November 2007

Abstract: The square-wave voltammetric technique was used to explore the adsorption properties of the astemizole drug. The analytical methodology used was based on the adsorptive preconcentration of the drug on a hanging mercury drop electrode (HMDE), followed by the electrochemical reduction process which yielded a well-defined cathodic peak at −1.184 V (vs. the Ag/AgCl electrode). To achieve high sensitivity, various experimental and instrumental variables were investigated such as the supporting electrolyte, pH, accumulation time and potential, drug concentration, scan rate, SW frequency, pulse amplitude, convection rate, and the working electrode area. Under the optimized conditions, the AdSV peak current was proportional over the analyte concentration range of 5 × 10⁻⁷ to 2.5 × 10⁻⁶ mol L⁻¹ (r = 0.998) with the detection limit of 1.4 × 10⁻⁸ mol L⁻¹ (6.4 ng mL⁻¹). The precision of the proposed method in terms of RSD was 2.4 %, whereas the method accuracy was indicated by the mean recovery of 100.1 %. Possible interferences of several substances usually present in the pharmaceutical tablets and formulations were also evaluated. The applicability of this electroanalytic approach was illustrated by the determination of astemizole in tablets and biological fluids.

Keywords: adsorptive stripping voltammetry - astemizole - tablet - biological fluids

Full paper is available at www.springerlink.com.

DOI: 10.2478/s11696-008-0041-z

Chemical Papers 62 (4) 339–344 (2008)