RP-HPLC method for the quantitative determination of fexofenadine hydrochloride in coated tablets and human serum

Abstract

Fexofenadine is a non-sedative and selective peripheral H₁ receptor antagonist prescribed for allergic rhinitis and chronic urticaria. This article deals with a simple, feasible, and sensitive isocratic reverse-phase high-performance liquid chromatographic method for the determination of fexofenadine hydrochloride in bulk drug, pharmaceutical dosage forms and in human serum. The chromatography was carried out at 20 ± 2°C using two different chromatographs and five different stationary phases. The isocratic mobile phase was phosphate buffer pH 7.4 and methanol (methanol–phosphate buffer, 35:65, v/v), detection was made at 218 nm and the mobile phase flowed at 1 ml min⁻¹. Validation parameters included linearity, accuracy, precision, specificity, limit of detection (LOD), limit of quantification (LOQ), and robustness over a linearity range 5–15 μg ml⁻¹ according to the ICH guidelines (r > 0.9999), the inter- and intra-day precisions were relative standard deviation (RSD) < 0.8%. The system suitability was scrutinized by capacity factor, tailing factor, and number of theoretical plates (capacity factor > 2.0, tailing factor ≤ 2.0, and theoretical plates > 2000). The retention time for five different stationary phases ranged from 3.78 to 4.15 min. The LOD and LOQ for the procedure were executed on samples containing very low concentrations of analytes on two different commercial brands of detectors.