Posted by admin on Oct 1, 2013 in |
The present study deals with the formulation and evaluation of gastroretentive floating tablets of dextromethorphan. Dextromethorphan is a highly potent and commonly used antitussive agent. It has no narcotic, analgesic or addictive properties and its potency as an antitussive agent is almost equal to that of codeine. The purpose of this research is to increase the gastric residence time by preparing gastroretentive floating tablets whereby making it available at its site of absorption and to achieve an extended action for a time period of 12 hrs. Dextromethorphan floating tablets were prepared by direct compression method using various grades of METHOCEL, POLYOX and CARBOPOL with three different concentrations. Preformulation studies were carried out and the compatibility of the drug with the excipients was confirmed through differential scanning calorimetry studies. The prepared gastroretentive floating tablets were evaluated for uniformity of weight, hardness, friability, density, drug content, floating lag time, floating time, swelling index and in vitro dissolution studies. The optimized formulations F3, F5 and F11 showed a floating time more than...
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Posted by admin on Oct 1, 2013 in |
In the present work in mathematical modeling, quantitative structure activity relationship (QSAR) studies were performed on some 5,6-dihydro-2-pyrones derivativesusing statistical work.Using only 4 topological and physico-chemical molecular descriptors, we have achieved 84.81% correct classification of the compounds with and without its activity.A heurisimatedtic algorithm selects the best multiple linear regression(MLR) equation showed the correlation between the observed values and the estimated values of activity is very good(R=0.9209, R2 =O.8481, PRESS=0.7312, 14Rcv2″> =0.8210, SPRESS =0.2074). The results are discussed in the light of the main factors that influence the inhibitory activity of the HIV-1 protease....
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Posted by admin on Oct 1, 2013 in |
A very simple and selective U. V. Method was developed and validated for the estimation of Atovaquone in pure form and the nanosuspension. The adequate drug solubility and maximum assay sensitivity was found in 8.00 Ph IPA Phosphate Buffer in 40:60 ratios v/v. The absorbances were measured at the λmax. of 494 nm in the wavelength range of 200-800 nm. The linear calibration range was found to be 20-140 µg/ml. The same method was applied and validated for the determination of Atovaquone in nanosuspensions. Also no interference was found from the excipients added to the nanosuspensions at the selected wavelength of 494 nm and at the analysis condition .It was found that the developed method was accurate, sensitive, precise, robust and reproducible. It can be applied directly for the estimation of drug containing the pharmaceutical...
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Posted by admin on Oct 1, 2013 in |
The aim of this study was to investigate the physicochemical properties of amlodipine besylate tablets. Tablets containing 5 mg of amlodipine besylate were prepared using Generally Regarded as Safe (GRAS) excipients. Preformulation studies were carried out using Fourier Transform Infrared (FTIR) spectroscopy and High Performance Liquid Chromatography (HPLC). Dissolution studies were performed to assess biowaiver criteria for Biopharmaceutical Classification System (BCS) Class I drug. Both the test and reference products conformed to pharmacopoeial requirements for physical parameter of tablets. FTIR studies revealed that there was no interaction between drug and excipients used in the test product. The percentage of drug remaining in the samples, subjected to the accelerated condition, complied the range specified in the United States Pharmacopeia (USP) monograph of amlodipine besylate. The dissolution of both the products was found to be more than 85 % in pH 1.2 buffer at the interval of 15 min. However, in pH 4.5 and pH 6.8 buffer media, only test product released more than 85 % drug, whereas the reference product...
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Posted by admin on Oct 1, 2013 in |
Objective: Recently, natural plants have received much attention as sources of biological active substances including antioxidants. In the present study we investigated In-vitro antioxidant activity of hexane, ethyl acetate and ethanol extracts of Solanum sisymbrifolium aerial parts. Methods: In-vitro antioxidant activity was evaluated for extracts by using free radicals Superoxide (Riboflavin photo reduction method) and DPPH (The scavenging activity for DPPH free radicals was measured according to the procedure described by Bracaand Sanja). Results: The selected plant extracts produced concentration dependent percentage inhibition of different free radicals and produced maximum activity at a concentration of 800µg and there after the percentage inhibition was raised gradually to its maximum level with higher concentrations. Conclusion: In the present study we found that the extracts of Solanum sisymbrifolium showed good antioxidant activity. Among the three extracts, hexane extract showed better activity than the other extracts on the tested super oxide free radical. The order of activity is in the following manner: Ascorbic acid >hexane extract > ethyl acetate extract> ethanol extract. Ethanol...
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