High-performance liquid chromatographic determination of acid-catalyzed degradation products of methyl carboprost in a polymeric controlled-release device

A normal-phase high-performance liquid chromatographic method was used for the determination of methyl carboprost and acid-catalyzed degradation products in a polymer-based, controlled release dosage form. A reversed-phase method was used to isolate sufficient quantities of the degradation products to determine their identity. Degradation of methyl carboprost under acidic conditions results in epimerization and dehydration, to several isomers, at the tertiary allylic hydroxyl group. Mass balance was 94% for a sample allowed to degrade 50%. These compounds were observed to form in the polymer-based, controlled release dosage form. For the determination of methyl carboprost in the dosage form, the method was found to be linear, precise with a relative standard deviation of 2% and to have an average recovery of 99.2%.