Comparative determination of halofantrine tablets by titrimetry, spectrophotometry and liquid chromatography

Abstract

Comparative determination of halofantrine tablets by titrimetry, ultraviolet spectrophotometry and liquid chromatography (LC) is described. Non-aqueous tirimetry on halofantrine hydrochloride tablets was carried out using glacial acetic acid as solvent, perchloric acid as titrant and crystal violet as indicator. Simultaneous potentiometric monitoring of end point delineated an exact color shade of indicator at the end point. Direct measurement of methanol solution, at 254nm, was adopted for UV spectrophotometric method while reversed-phase liquid chromatographic (LC) method employed a C8 column (4.6mm x 25cm) with mobile phase consisting of methanol / 0.05 M NaH2PO1 (76:24. v/v) containing 55mmol/L perchloric acid (pH 3.4) at a flow rate of 1 ml / min. The three methods gave precise and accurate results. Mean percentage recover) were obtained respectively as 100.73± 0.41, 100.36±0.79 and 99.93±3.74 % while coefficient of variation were 0.41. 1.36 and 3.74 % for non-aqueous. UV spectrophotometry and LC. The three methods were successfully applied to analysis of halofantrine tablets (Halfan®) and showed no statistically significant difference in accuracy (P>0.05, ANOVA). Validated assay methods for halofantrine tablets have been developed. The titrimetric and spectrophotometry methods arc of equivalent accuracy with the liquid chromatographic method and could be used for routine quality control of halofantrine tablets where LC method is not readily available.