Abstract

Microspheres containing indinavir sulfate were prepared by the emulsion solvent evaporation technique using surfactant sorbitan monooleate 80. The evaluation reports for Fourier-transform infrared spectroscopy and X-ray diffraction spectroscopy were taken to see whether the surfactant altered the physicochemical features of the produced microspheres. Scanning electron microscopy was used to observe the surface topography of the microspheres. When sorbitan monooleate 80 was employed at dissimilar concentrations, the sorbitan monooleate 80 microspheres had higher concentrations that resulted in smaller particle size as compared to the lower concentrations of sorbitan monooleate 80 microspheres, therefore, the faster release rate was observed by utilizing a higher concentration of sorbitan monooleate 80. The microspheres entrapped 71 % to 96 % of the drug and released it for up to 7 h. X-ray diffraction revealed a decrease in the crystallinity of the drug. Scanning electron microscopy analysis revealed the spherical and after dissolution detected porous structure of microspheres. The excellent fit release kinetics is accomplished with the zero-order, Higuchi plot followed by first-order, Hixson-Crowell and Korsmeyer-Peppas equations. As a result, the drug indinavir sulfate release rate was influenced by surfactant concentrations, drug-polymer ratio, particle size and the diffusion release mechanism.