Spectrophdtometric Determination of Hydralazine Hydrochloride, Oxprenolol Hydrochloride & Chlorthalidone in Combination and for Oxprenolol Hydrochloride as Single Component Dosage Form

Abstract

Three component tablet assay and single component tablet assay are presented. The first is performed for hydralazine hydrochloride, oxprenolol hydrochloride & chlorthalidone existing in a ratio 2.5: 8: 1 respectively. Hydralazine is estimated through absorbance measurements at 314 nm, D₁ at 315 nm or D₂-at 316 nm. Modified Vierordts method-after absorbance correction from hydralazine hydrochloride interference and also D₂ methods are applied for oxprenolol hydrochloride assay. Chlorthalidone, the minor component, is assayed after its extraction using D₁ or D₂ measured at 282 nm & 268–284 nm respectively. For single tablet assay, oxprenolol hydrochloride is assayed using A_max at 272 nm, D₁-measurement at 252–274 nm & D₂-measurement at 260–278 nm. The first method is suffering from systematic error corrected by the latter two methods.