Quantitative determination of isoconazole nitrate and diflucortolone valerate in their binary mixtures by derivative uv spectrophotometry and HPLC

In this study, in combined creams which contain an antifunfal drug Isoconazole nitrate(ISO) and antiinflammatory drug, Diflucortolone valerate (DIF), simultaneous quantitative determination of active substances were determined Derivative UV spectrophotometry and obtained results were compared with those obtained developed HPLC method. In spectrophotometric method, quantitative determinations were performed 289.2 nm (2nd derivative, n=5) for ISO and 262 nm (2nd derivative, n=9) for DIF and ethanol was used as solvent. Linear calibration ranges were 100-500 µg/ml and 5-25 µg/ml for ISO and DIF, respectively. Recoveries and RSD values were 99.67%, 102.03% and 2.03%, 3.67% for ISO and DIF, respectively. An HPLC method was developed with the use of Phenomenex column (250x4.6 mm), metanol: deionised water (80:20) as mobile phase, at 1 ml/min flow rate, and 220 nm wavelenght was used for detection. Retention times were 1.8 and 5.4 min. for ISO and DIF, respectively. In HPLC method, linear calibration ranges, recoveries and RSD values were 15-240 µg/m, 6-60 µg/ml, 98.46% 99.41%, 2.8%, 1.63% for ISO and DIF, respectively. Results obtained from both methods were statistically compared with each others and it was observed that there is no difference between these results.