Simultaneous high-performance liquid chromatographic determination of propoxyphene and acetaminophen in pharmaceutical preparations.

A normal-phase high-performance liquid chromatographic method, using a 3.3 cm x 4.6 mm silica column (3 microns packing) and an ammonium hydroxide-methanol-dichloromethane mobile phase, has been developed to separate propoxyphene and acetaminophen in less than 5 min. Quantitative recovery of both compounds from various pharmaceutical preparations was achieved, following a single dilution scheme. The method is stable, reproducible, and selective.