Microencapsulation of ibuprofen and Eudragit (R) RS 100 by the emulsion solvent diffusion technique

Department of Pharmacy, University of Durban-Westville, Private Bag X54001, 4000, Kwazulu-Natal, Durban, South Africa.
International Journal of Pharmaceutics (Impact Factor: 3.79). 06/2001; 218(1-2):1-11. DOI: 10.1016/S0378-5173(00)00686-4
Source: PubMed

ABSTRACT The emulsion solvent diffusion was employed to prepare modified release microspheres of ibuprofen. The technique was optimised for the following processing variables: the absence/presence of baffles in the reaction vessel, agitation rate and drying time. Thereafter, the influence of various formulation factors on the microencapsulation efficiency, in vitro drug release and micromeritic properties was examined. The variables included the methacrylic polymer, Eudragit(R) RS 100, ibuprofen content and the volume of ethanol used during microencapsulation. The results obtained were then interpreted on a triangular phase diagram to map the region of microencapsulation, as well as those formulations that yielded suitable modified release ibuprofen microspheres.

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    • "Certain biologically tolerable synthetic polymers such as polyacrylate copolymers (Eudragit), polycaprolactones, polyaspartamides, or polyamidoamines are also eligible. Perumal [15] studied the effect of formulation parameters and the technical design of reaction vessel on the properties of microspheres prepared from the ibuprofen model drug and a methacrylic polymer Eudragit® RS 100. Applying side baffles along the circumference of the vessel considerably improved the particle size attributes (lower mean size, narrower size distribution and more regular shape) and the yield of microspheres. "
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    • "Second, alginate possesses mucoadhesive properties which could increase the contact time between microcapsules and absorptive sites, and therefore, could enhance the uptake of encapsulated drug (Guan et al., 2001). Third, biodegradable alginate microcapsules may show variable release kinetics (Perumal, 2001). Fourth, the low toxicity and low immunogenicity of alginate make this polymer a safe matrix (Chan et al., 2002). "
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