Study of the formulation parameters affecting the preparation of microencapsulated ion-exchange resins containing venlafaxine hydrochloride
1 Department of Pharmaceutics, Shen Yang Pharmaceutical University, Shen Yang 110016, People's Republic of China, 2 Institute of Material Medical, Shen Yang No.1 Pharmaceutical Factory, Shen Yang, 110023, People's Republic of China,
W S Pan Department of Pharmaceutics, Shen Yang Pharmaceutical University, Shen Yang 110016, People's Republic of China E-mail: [email protected]
The objective of this study was to obtain an optimum formulation for microencapsulating venlafaxine hydrochloride ion-exchange resins. This was achieved by investigating various factors which influenced the drug release. The percentage of drug released was used as an index to investigate the individual factor. The optimum coating formulation was acquired by orthogonal experiments in which the concentration of coating material in acetone was 3%, the ratio of drug-resin complexes to coating materials was 8:1 and the ratio of plasticity-agent to coating material was 5%. The results indicated that the use of ion-exchange resins along with a suitable coating material would be a feasible way to prepare a marked prolonged release type of microcapsules by the emulsion solvent diffusion method.