UV Spectroscopy

To develop a simple, precise, accurate, and stability indicating a UV-method for estimation of Clotrimazole. In bulk and formulated dosage form. The method was under subjected to stress degradation at different conditions recommended by the International Conference on Harmonization (ICH). The drug samples are generated and used for the degradation studies. The λmax of the Clotrimazole was found to be 220 nm. The linearity of calibration curve (Absorbance Vs Concentration) in pure solution was checked over the concentration ranges of about 5-30μg/ml for Clotrimazole respectively, with the correlation coefficient higher than 0.999. The regression equation of the curve was Y = 0.0168x + 0.0041. The % RSD was found to be within the limit as per ICH guidelines. The obtained percentage recovery of Clotrimazole was found to be within the limit 100% ± SD. The proposed method can be successfully applied for the method development, validation and stress degradation studies of Clotrimazole. The percentage degradation limit should be 5-20%. The drug Clotrimazole was found to be within the limit.

Isosorbide Dinitrate (ISD) is a moderate to long acting oral organic nitrate which acts as a vasodilator profoundly used in the treatment of angina pectoris, a condition which occurs when the oxygen supply to the myocardium is insufficient for its needs. It is slightly soluble in water and propanol, sparingly soluble in ethanol and freely soluble in methanol. The most economical solvent Distilled water was choosen as a solvent. The drug has absorption maximum (method A) at 304nm, Area under curve (method B) at 300-310 and first order derivative method (method C) at 287nm. Linearity for all three methods was found in the range of 5-25 μg/ml with Correlation coefficient is 0.999, Standard error is 0.001. The drug sample was analyzed by UV spectroscopy using distilled water as solvent and the average content of drug present in the formulation was found to be 99.7%. The % recovery of accuracy studies was found to be 99.1 % for method A, 101.5 % for method B, 100.6 % for method C. The %RSD of precision was found to be 1.11% for intraday, 1.22 % for inter day. The force degradation studies of Isosorbide Dinitrate was done on Stress degradation by hydrolysis under alkaline condition by using 0.1N NaOH was found to be 10.09% for 24hrs, 13.3% for 3days, 14.2% for 5days .Stress degradation by hydrolysis under acidic condition by using 0.1N HCl and degradation was found to be  2.68% for 24hrs, 9.7% for 3days, 11.9% for 5days.  Oxidative degradation was done by using hydrogen peroxide (3%v/v) and degradation was found to be 3.22% for 24hrs, 5.06% for 3days, and 8.29% for 5days. The proposed methods can be successfully employed for quality control during manufacture and for assessment of the stability of Isosorbide Dinitrate in bulk samples and its tablet dosage forms.

Simple area under curve spectrophotometric method for determination of Cefixime and Linezolid in bulk and tablet formulation was developed and validated as per ICH guidelines. The lmax of Cefixime and Linezolid were found to be 289nm and 257nm respectively. The linearity range was found 2-12μg/ mL for Cefixime and 5-30μg/mL for Linezolid. In the tablets dosage form Cefixime and Linezolid were estimated as 99.92% and 99.94% respectively. The lower limit of detection (LOD) for Cefixime and Linezolid was found to be 0.039μg/ml and 1.11μg/ml respectively.and the limit of quantization (LOQ) was determined as the lowest concentration for Cefixime and Linezolid was found to be 0.118μg/mL and 3.37μg/ml respectively. The validated spectrophotometric method employed proved to be simple, economical, precise and accurate.