Drug release through aqueous-based film coatings of acrylate-methacrylate, a water-insoluble copolymer

Abstract

An aqueous-based system of a water-insoluble acrylate-methacrylate copolymer was prepared by a coarcevation technique. The composition of the fluid included ethanol (10 ml), polymer (5 g) and a non-solvent, water (90 ml). Polymer film coatings were applied on a porous substrate (Whatman No. 1 filter paper) by immersion of the substrate (10 s) in the fluid. After drying, the performance of the film coatings as barriers in drug release studies compared favourably with that of film coatings cast from ethanol and were considerably more permeable than those cast from acetone. This difference relates to the higher polarity of water or ethanol compared with acetone. The indication is that the aqueous-based system could be substituted for the more expensive ethanol in the polymeric coating of drug particles.