Author(s): Afaf Abou-elkheir*, HanaaSaleh, Magda M. El-henawee, BasmaEl-sayed Ghareeb
Four methods are developed for simultaneous determination of Miconazole Nitrate and Hydrocortisone without previous separation. The first method depends on first derivative of the ratios spectra by measurements of the amplitudes at 233, 285 nm for Miconazole nitrate and 240,256 nm for Hydrocortisone. The second method depends on measuring the absorbance at the isosbestic point at 231.5 nm for the total concentration of both drugs while the concentration of Hydrocortisone is determined by direct spectrophotometric method at λ max 241.5 nm in the presence of Miconazole nitrate, the concentration of Miconazole nitrate is calculated by subtraction. The third method is factorized absorptivity method at which both drugs are determined at more than one isosbestic point 217.5, 224nm.The fourth method involved application of the bivariate calibration algorithm for spectrophotometric simultaneous determination of the mixture. The suggested procedures are validated using laboratory prepared mixtures and are successfully applied for the analysis of pharmaceutical preparations. The methods retained their accuracy and precision when the standard addition technique is applied. The results obtained are statistically analyzed and compared with those obtained by the manufacturer method.