Percolation theory : application to the study of the release behaviour from inert matrix systems

Abstract In the present paper, release profiles obtained from matrix tablets prepared with Eudragit ® RS-KC1 and a usual eccentric machine were studied. The results were in agreement with previously reported release studies for compacts prepared using a hydraulic press. The most outstanding aspect is the study of the influence of the particle size of drug and excipient on the release behaviour of the matrices, and its evaluation on the basis of percolation theory. The influence of soluble drug loading has also been studied. This new theory has been shown to be a useful tool to explain the release profiles from inert matrix compressed tablets.