2ND DERIVATIVE SPECTROPHOTOMETRIC DETERMINATION OF THE DEGRADATION PRODUCTS OF DICLOFENAC SODIUM IN GEL-OINTMENT

A second derivative spectrophotometric method has been developed for t he determination of the degradation products from diclofenac sodium in gel-ointment. The amplitudes in the second derivative spectra at 260 and 265 nn were selected to determine oxindol. A linear relationship b etween derivative amplitudes and a concentration of compounds was foun d. The detection limit of oxindol was estimated to be 0.01% with respe ct to the gel-ointment. The method is rapid, simple, specific and does not require any preliminary separation or treatment of the samples. T he proposed method is statistically validated and found to be accurate , sensitive and reproducible.