Development and validation of a liquid chromatographic method for fexofenadine hydrochloride in capsules

This paper describes the development and validation of a new, simple, fast, and sensitive liquid chromatographic method for the determination of the antihistamine fexofenadine. Although widely used in the treatment of allergic diseases, fexofenadine is not listed in any pharmacopeia, and there are few methods in the literature for its quantitation in pharmaceutical dosage forms. In this work, a LiChrospher 100 RP-18 (250 x 4.0 mm, 5 microm) column was used as the stationary phase, and acetonitrile-5mM ammonium acetate buffer (50 + 50, v/v) at pH 3.2 was the mobile phase. Through the evaluation of the analytical parameters, it was shown that the method is linear (r = 0.9999) at concentrations ranging from 20.0 to 80.0 microg/mL, precise (intraday relative standard deviation [RSD] values = 0.85, 0.40, and 0.81%; interday RSD = 0.77%), accurate (mean recovery = 99.05%), specific, and robust. The detection and quantitation limits are 0.3409 and 1.033 microg/mL, respectively. These low values show the good sensitivity of the proposed method.