The evaluation of Eudragit microcapsules manufactured by solvent evaporation using USP Apparatus 1

Khamanga, S.M.M. and Parfitt, N. and Nyamuzhiwa, T. and Haidula, H. and Walker, R.B. (2009) The evaluation of Eudragit microcapsules manufactured by solvent evaporation using USP Apparatus 1. Dissolution Technologies, 16 (2). pp. 15-21. ISSN 1521-298X



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The objectives of this study were to prepare microcapsules containing verapamil and propranolol and to evaluate the kinetics and mechanism of drug release from the microcapsules using USP Apparatus 1. The effects of polymer concentration and polymer type on the cumulative amount of drug released were evaluated. The microcapsules were manufactured using Eudragit RS and RL polymers by solvent evaporation with the ultimate aim of prolonging drug release. Twenty-four formulations were prepared using different drug/polymer ratios. The effects of polymer type and polymer/drug ratios on the size, flow properties, surface morphology, and the release characteristics of the microcapsules were examined. The effects of drug inclusion methods on drug loading, encapsulation efficiency, and release properties of the complex microcapsules were also investigated. The formulations containing drug/polymer ratio 1:4 (w/w) were the most appropriate with respect to encapsulation efficiency (70%), flow properties (HR = 1.2), drug loading (15–20%), and drug release characteristics, in all cases. The release kinetics from the different formulations followed mainly a diffusion-controlled mechanism.

Item Type:Article
Uncontrolled Keywords:USP Apparatus 1; microcapsules; drug release; verapamil; propranolol; Eudragit; solvent evaporation; kinetics
Subjects:Y Unknown > Subjects to be assigned
Divisions:Faculty > Faculty of Pharmacy
ID Code:1498
Deposited By: Mrs Eileen Shepherd
Deposited On:16 Sep 2009
Last Modified:06 Jan 2012 16:20
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