Cherukuru Nagaraju

Two novel methods having requisite precision, accuracy, specificity and robustness were developed and validated for quantitative determination of Apixaban in pharmaceutical dosage forms. The first method was based on isocratic reverse phase liquid chromatography using Sunfire C18, 150mm×4.6mm, 5µ and mobile phase consists of Buffer: acetonitrile (60:40) at a flow rate 1ml/min and detection was achieved photodiodide array detector set at 280 nm. The response was linear range of 5-50 µg/ml (R2 =0.9998). The second spectrophotometric method involves detection at 280 nm. The calibration curve range between 5-50 µg/ml (R2 =0.9999). Validation of method was carried out fulfilling ICH guidelines. Both the methods were applied without any interference from excipients, for determination of drug in coated tablets. It is suggested that the proposed HPLC and UV spectrophotometric methods could be used routine quality control and dosage form assay of Apixaban.

To develop a fast and sensitive  UV spectrophotometric method for the quantitative estimation of Formaldehyde in Rivastigmine tartrate drug substances and validate as per ICH guidelines. The method was based upon the observation, that a characteristic colourresults upon addition of  solution of Pentane-2,4-dione , also known as acetylacetone . In acetic acid and ammonium acetate buffer condition, acetylacetone and formaldehyde react to form dimethyl pyridine. Dimethyl pyridine is slightly yellow and its absorption maximum in aqueous solution is λ 420 nmin Rivastigmine tartrate drug substance.The developed method resulted in Formaldehyde exhibiting linearity in the range 0.975 to 234 µg/g. The Intraday and interday precision is exemplified by relative standard deviation of 0.562 % and 0.757%. Percentage Mean recovery was found to be in the range of 98‐101%, during accuracy studies. The limit of detection (LOD) and limit of quantitiation (LOQ) were found to be 1.3 µg/g and 3.9 µg/g respectively.The present work was aimed to develop a visible spectrophotometric method, which is simple, sensitive, accurate and cost effective to evaluate the quality of the bulk drugs.