Determination of phenylpropanolamine hydrochloride as benzaldehyde in pharmaceutical preparations using normal-phase high-performance liquid chromatography

Abstract

A rapid, accurate and precise method for the determination of phenylpropanolamine hydrochloride in a cough-mixture is described. The method is based on the determination by normal-phase HPLC of benzaldehyde formed after periodate oxidation. The method is applicable to other phenalkanolamine drugs that yield benzaldehyde on periodate oxidation, e.g., ephedrine, and has also been found suitable for other dosage forms, such as syrups, powders, tablets and capsules. The high sensitivity of the method makes it especially useful for individual dosage unit assays.