Validated ultra-performance liquid chromatographic and thin-layer chromatographic densitometric methods for the determination of paracetamol, pamabrom, and pyrilamine maleate

Abstract

Two chromatographic methods were developed for the simultaneous determination of paracetamol, pamabrom, and pyrilamine maleate in bulk and combined pharmaceutical dosage form. The first method is an ultra-performance liquid chromatographic (UPLC) method, in which separation was carried out by gradient elution using C18 column and a mobile phase composed of solution A (acetonitrile) and solution B (phosphate buffer) (pH 3.5). The elution started with 20% (by volume) acetonitrile ramped up linearly to 100% in 2 min, then kept constant till the end of the run at a flow rate of 1.5 mL min?1 and ultraviolet (UV) detection at 277 nm. The second method depends on the densitometric determination of thin-layer chromatograms of the three drugs. Separation was carried out at 275 nm using chloroform?acetonitrile (15:35, v/v) as the mobile phase. The proposed methods were validated according to the International Conference on Harmonisation (ICH) guidelines. Beers law was obeyed in the range of 5100 ?g mL?1 for paracetamol and 0.520 ?g mL?1for pamabrom and pyrilamine maleate, respectively, with mean recoveries of 98.40?100.32% 0.551?0.771 for the UPLC method. Linearity of the thin-layer chromatographic method was achieved in the range of 10?280, 5?45, and 120 ng per spot of the three drugs with mean recoveries of 98.75?100.30% 0.971?1.061, respectively. The two methods were successfully applied for the simultaneous determination of the cited drugs in their laboratory-prepared mixtures and pharmaceutical dosage form with good accuracy and precision. The results obtained were compared with those of the reported method and found to be in good agreement. Akadmiai Kiad, Budapest.