RESIN BEAD DETECTION AND SPECTROPHOTOMETRIC DETERMINATION OF OXYPHENBUTAZONE WITH P-DIMETHYLAMINOCINNAMALDEHYDE - APPLICATION TO BULK DRUG AND DOSAGE FORMS

An analytical method for resin bead detection and spectrophotometric d etermination of oxyphenbutazone with p-dimethylaminocinnamaldehyde as a reagent is described. Acid hydrolysed product of oxyphenbutazone pro duced a red color product with p-dimethylaminocinnamaldehyde that abso rbs maximally at 520 nm. The detection limit is 0.8 mug in resin phase and 4.0 mug in aqueous phase. Beer's law is obeyed in the concentrati on range of 0.4-4.0 mug/ml of oxyphenbutazone. The method is unaffecte d by the presence of acetylsalicylic acid, salicylamide, phenylbutazon e and number of other excipients but paracetamol gives a positive reac tion and novalgin being reductone interferes with the test, both shoul d be removed by extraction with dilute sulfuric acid.