Validation of Methods for the Assay of Flurbiprofen and Flurbiprofen Sodium, Related Compounds and Volatile Impurities in Raw Materials and Tablets

A high performance liquid chromatographic method has been developed for the assay of flurbiprofen, or flurbiprofen sodium and related compounds in drug raw materials and tablets. A phenyl column with a mobile phase of acetonitrile: 1.0% acetic acid (60:40) provide for the resolution of twenty-one related compounds from the drug. Minimum detectable levels of the related compounds are 0.01% and minimum quantifiable levels are 0.1% or less. Total impurity levels in seven raw materials ranged from 0.0 to 0.6%. One impurity, 2-(4-biphenylyl) propionic acid, is present in most samples at about 0.3%. A gas chromatographic method was developed for organic volatile impurities