A validated HPLC method for assay of morphine hydrochloride and hydromorphone hydrochloride in pharmaceutical injections

A sensitive and rapid routine HPLC method is proposed for quantitative esti mation of morphine hydrochloride and hydromorphone hydrochloride in pharmac eutical dosage forms. The drugs were chromatographed on a C-18 reversed-pha se column; the mobile phase was acetonitrile-water, 35:65 (v/v), containing sodium dodecyl sulphate (0.5%, w/v), as ion pairing reagent, and acetic ac id (0.4% v/v). Detection was at 230 nm. The optimized method was validated, and linearity (r > 0.999) precision, an d accuracy were found to be acceptable within the concentration ranges 86 - 124 mug mL(-1) for morphine hydrochloride and 60 - 180 mug mL(-1) for hydr omorphone hydrochloride. The method is being used to investigate the stability of morphine hydrochlo ride and hydromorphone hydrochloride in solutions used for intramuscular in jection.