RETARDATION OF NITROFURANTOIN RELEASE BY COACERVATION

Document Type : Original Article

Authors

1 Departments of Industrial Pharmacy, Faculty of Pharmacy, Assiut University, Assiut, Egypt

2 Departments of Pharmaceutics, Faculty of Pharmacy, Assiut University, Assiut, Egypt

Abstract

Gelatin-acacia coacervation was employed to microencapsulate paraffin oil and soft paraffin droplets containing suspended nitrofurantoin, and for direct encapsulation of the drug. Dissolution characteristics of the encapsulated paraffin suspensions of nitrofurantoin, the directly encapsulated drug and nitrofurantoin powder were compared in buffer solutions of pH 1.12 and 7.2. The most rapid dissolution was shown by the nitrofurantoin powder followed by the directly encapsulated drug, the emulsified paraffin oil suspension of nitrofurantoin.
The drug was released from oil-containing microcapsules in successive stages representing initial release from capsular layer followed by sustained release from the oily core material.
Formalization of the gelatin-acacia coacervates should be allowed for enough time in order to obtain enteric protection.
No correlation was found between the equilibrium solubility of the drug in the buffer and the corresponding release profile in the same buffer.
The rate of release was slower as the viscosity of the core oil increased.