<abstract xmlns="http://www.w3.org/1999/xhtml"><p>Percolation theory has been applied to study the drug release behaviour in multicomponent inert matrices containing ethylcellulose as a matrix forming polymer. Global influence of major formulation factors such as polymer viscosity, polymer particle size, drug and filler solubility and porosity of the tablets in drug release kinetics has been studied for the first time. Batches containing three viscosity grades of Ethocel™, microcrystalline cellulose (MCC) and lactose as fillers, a lubricant and flow aid mixture and three drugs with different solubility have been manufactured. For some batches, compression pressure was varied in order to obtain matrices with five levels of initial porosity. The behaviour of inert matrices was explained based on the percolation ranges of the main components of the formulation. The effect of the porosity percolation threshold was observed and the existence of a tricoherent drug-polymer-filler system is hypothesized.</p></abstract>

Percolation theory has been applied to study the drug release behaviour in multicomponent inert matrices containing ethylcellulose as a matrix forming polymer. Global influence of major formulation factors such as polymer viscosity, polymer particle size, drug and filler solubility and porosity of the tablets in drug release kinetics has been studied for the first time. Batches containing three viscosity grades of Ethocel™, microcrystalline cellulose (MCC) and lactose as fillers, a lubricant and flow aid mixture and three drugs with different solubility have been manufactured. For some batches, compression pressure was varied in order to obtain matrices with five levels of initial porosity. The behaviour of inert matrices was explained based on the percolation ranges of the main components of the formulation. The effect of the porosity percolation threshold was observed and the existence of a tricoherent drug-polymer-filler system is hypothesized.

Critical points in ethylcellulose matrices: Influence of the polymer, drug and filler properties

Department of Pharmacy and Pharmaceutical Technology University of Seville, 41012 Seville Spain

Colorcon Inc. Global Headquarters Harleysville, PA 19438, USA

Acta Pharmaceutica

Percolation theory has been applied to study the drug release behaviour in multicomponent inert matrices containing ethylcellulose as a matrix forming polymer....

Critical points in ethylcellulose matrices: Influence of the polymer, drug and filler properties

Published Online: Mar 12, 2013

Page range: 115 - 129

DOI: https://doi.org/10.2478/acph-2013-0005

Keywords
inert matrices, critical points, percolation theory, sustained release

This content is open access.

Critical points in ethylcellulose matrices: Influence of the polymer, drug and filler properties

Published Online: Mar 12, 2013

Page range: 115 - 129

DOI: https://doi.org/10.2478/acph-2013-0005

Keywordsinert matrices, critical points, percolation theory, sustained release

This content is open access.

Keywords
inert matrices, critical points, percolation theory, sustained release