Faculty of Pharmacy, Rhodes University, PO Box 94, Grahamstown 6140, South Africa
Khamanga, S.M., Faculty of Pharmacy, Rhodes University, PO Box 94, Grahamstown 6140, South Africa; Walker, R.B., Faculty of Pharmacy, Rhodes University, PO Box 94, Grahamstown 6140, South Africa
Captopril (CPT) microparticles were manufactured by solvent evaporation using acetone (dispersion phase) and liquid paraffin (manufacturing phase) with Eudragit® and Methocel® as coat materials. Design of experiments and response surface methodology (RSM) approaches were used to optimize the process. The microparticles were characterized based on the percent of drug released and yield, microcapsule size, entrapment efficiency and Hausner ratio. Differential scanning calorimetry (DSC), Infrared (IR) spectroscopy, scanning electron microscopy (SEM) and in vitro dissolution studies were conducted. The microcapsules were spherical, free-flowing and IR and DSC thermograms revealed that CPT was stable. The percent drug released was investigated with respect to Eudragit® RS and Methocel® K100M, Methocel® K15M concentrations and homogenizing speed. The optimal conditions for microencapsulation were 1.12g Eudragit® RS, 0.67g Methocel® K100M and 0.39g Methocel® K15M at a homogenizing speed of 1643rpm and 89% CPT was released. The value of RSM-mediated microencapsulation of CPT was elucidated. © 2012 Informa UK Ltd All rights reserved.
captopril; oil; solvent; article; differential scanning calorimetry; drug coating; drug manufacture; drug release; emulsion; evaporation; in vitro study; infrared spectroscopy; melting point; microencapsulation; nonhuman; particle size; response surface method; scanning electron microscopy; thermography; viscosity; Angiotensin-Converting Enzyme Inhibitors; Calorimetry, Differential Scanning; Captopril; Microscopy, Electron, Scanning; Microspheres; Oils; Particle Size; Solvents; Spectrophotometry, Infrared