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Tropical Journal of Pharmaceutical Research
Pharmacotherapy Group, Faculty of Pharmacy, University of Benin, Benin City, Nigeria
ISSN: 1596-5996 EISSN: 1596-5996
Vol. 4, No. 1, 2005, pp. 369-375
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Bioline Code: pr05007
Full paper language: English
Document type: Research Article
Document available free of charge
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Tropical Journal of Pharmaceutical Research, Vol. 4, No. 1, 2005, pp. 369-375
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Formulation and in vitro Evaluation of Eudragit® Microspheres of Stavudine
Sunit Kumar Sahoo, Abdul Arif Mallick, BB Barik and Prakash Ch Senapati
Abstract
Purpose:
The aim of this study was to formulate and evaluate microencapsulated controlled release preparations of a highly water-soluble drug, stavudine, using Copolymers synthesized from acrylic and methacrylic acid esters (Eudragit RS 100 and RL 100) as the retardant material. .
Methods:
Microspheres were prepared by solvent evaporation method using an acetone / liquid paraffin system. Magnesium stearate was used as the droplet stabilizer and n-hexane was added to harden the microspheres. The prepared microspheres were characterized for their micromeritic properties and drug loading, as well by fourier transform infrared spectroscopy (FTIR), differential scanning calorimetry, x-ray powder diffractometry and scanning electron microscopy. The in vitro release studies were performed in pH 6.8, phosphate buffer.
Results:
The prepared microspheres were white, free flowing and spherical in shape. The drug-loaded microspheres showed 67-91% of entrapment and release was extended upto 6 to 8 h. The infrared spectra and differential scanning calorimetry thermographs showed stable character of stavudine in the drug-loaded microspheres and revealed the absence of drug-polymer interactions. X-ray diffraction patterns showed that there was decrease in crystallinity of the drug. Scanning electron microscopy study revealed that the microspheres were spherical and porous in nature.
Conclusion:
The best-fit release kinetics was achieved with Higuchi plot followed by zero order and First order. The release of stavudine was influenced by the drug to polymer ratio and particle size & was found to be diffusion controlled.
Keywords
stavudine, Eudragit, microspheres, controlled release, polymethacrylate.
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© Copyright 2002-2006. TJPR Faculty of Pharmacy, University of Benin, Benin City, Nigeria Alternative site location: http://www.tjpr.org
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