Asian Journal of Research in Chemistry

P. Nagaraju ¹, B. Sridhar ², P. Jitendra Kumar ³, U. Upendra Rao ¹, K. Hanumantha Rao ², P. N. V. Gopal ¹

Affiliations
1 Hindu College of Pharmacy, Amaravathi Road, Guntur – 522 002, Andhra Pradesh, IN
2 DCRM Pharmacy College, Inkollu, Andhra Pradesh, IN
3 Siddhartha Institute of Pharmacy, Sattenapalli, Andhra Pradesh, IN

Abstract

The present work describes a simple reverse phase HPLC method for the estimation of Atorvastatin calcium in bulk and pharmaceutical formulations. The estimation was carried out on phenomenex C₁₈ (250 × 4.6 mm, 5μ) column using a mobile phase containing of Acetonitrile: Ortho-phosphoric acid (0.1%): Tetrahydrofuran (48:0.04:52). The eluent was monitored at 244 nm. The results have been validated statistically and recovery studies confirmed the accuracy of proposed method.

Keywords

HPLC, Validation, Atorvastatin Calcium and Pharmaceutical Formulation.

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P. Nagaraju ¹, V. D. N. Srinivas ¹, S. V. N. Padma ¹, P. N. V. Gopal ¹, D. Mallikarjuna Rao ¹

Affiliations
1 Department of Pharmaceutical Analysis, Hindu College of Pharmacy, Amaravathi Road, Guntur, IN

Abstract

Over the past decade, cavity ring down spectroscopy has emerged as a powerful technique for performing direct absorption measurements using pulsed lasers. Cavity ring down spectroscopy has since been used from the ultraviolet to the mid-infrared. It is a direct absorption technique, which can be performed with pulsed or continuous light sources and has a significantly higher sensitivity than obtainable in conventional absorption spectroscopy. It can be used to measure the concentration of some light-absorbing substances. Typically, the substances to be measured are in gaseous form. This technique is most widely known as cavity ring-down spectroscopy, although the alternative, but more cumbersome, cavity ring-down laser absorption spectroscopy is preferred by some authors. Here we discuss about the experimental implementation of Cavity ring down spectroscopy and its application to a number of areas of research including laser diagnostics of hostile environments, reaction kinetics and spectroscopy, with particular emphasis on our ongoing studies of the fast (sub-nanosecond) pre dissociation of electronically excited states of small molecules and radicals.

Keywords

Cavity Ring Down Spectroscopy, Absorption Spectroscopy.

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P. Nagaraju ¹, Z. Vishnu Vardhan ², J. V. L. N. Seshagiri Rao ³

Affiliations
1 Hindu College of Pharmacy, Amaravathi Road, Guntur-522002 (Andhra Pradesh), IN
2 Department of Environmental Sciences, Acharya Nagarjuna University, Nagarjuna Nagar, IN
3 University College of Pharmaceutical Sciences, Andhra University, Visakhapatnam, IN

Abstract

A simple, sensitive and precise reverse phase high performance liquid chromatographic method has been developed for the simultaneous estimation of Atorvastatin calcium and Ezetimibe in pharmaceutical dosage forms. The mobile phase consisted of Acetonitrile: buffer (0.1% v/v ortho phosphoric acid, P^H-6) in the ratio 60:40 delivered at a flow rate of 1 ml/min and wavelength of detection at 232 nm. The retention times of Atorvastatin calcium and Ezetimibe were 3.7 min and 6.1 min respectively. The developed method was validated according to ICH guidelines. The proposed method can be used for determination of these drugs in combined dosage forms.

Keywords

Atorvastatin Calcium, Ezetimibe, RP-HPLC.

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P. Nagaraju ¹, D. Narendra ¹, P. Jitendra Kumar ¹, V. D. N. Srinivas ¹, S. V. N. Padma ¹

Affiliations
1 Hindu College of Pharmacy, Amaravathi Road, Guntur-522002, IN

Abstract

A reverse phase high performance liquid chromatographic method (HPLC) has been developed for the estimation of entacapone in its dosage forms using C₁₈ column. The mobile phase (acetonitrile and 20 mM potassium dihydrogen phosphate, P^H 3.5) was pumped at a flow rate of 1 ml/min in the ratio of 80:20 and the eluents were monitored at 320 nm. The intra- and inter- day variation was found to be less than 2% showing high precision of the assay method. The mean recovery of the drug from the solution containing 200 or 300 μg/ml was 99.66±1.20% indicating high accuracy. The proposed HPLC method may be used for determining entacapone in bulk drug samples or in pharmaceutical dosage forms.

Keywords

Estimation, Entacapone, Tablets and HPLC.

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