Development and validation of a dissolution method for warfarin sodium and aspirin combination tablets.

A dissolution method for warfarin sodium-aspirin combination tablets was developed which utilizes USP Apparatus 1 (baskets) at 50 rpm with 900 ml of phosphate buffer (pH 6.8; 0.05 M) medium at 37 degrees C. A reversed-phase liquid chromatographic method was also developed for the simultaneous determination of warfarin sodium, aspirin and salicylic acid on an octadecylsilica column using acetonitrile-tetrahydrofuran-glacial acetic acid-water (23:5:5:67, v/v/v/v) as the mobile phase with UV detection at 282 nm. Validation data were obtained which demonstrate that the dissolution methodology is accurate, precise, linear and rugged for the combination tablets.