Design and evaluation of layered diffusional matrices for zero-order sustained-release.
New layered matrix systems designed for zero-order sustained release are presented. The devices consist of a hydrophobic middle layer and press-coated hydrophillic and/or hydrophobic barrier layer(s). The systems overcome the inherent disadvantage of non-linear release associated with diffusion-controlled matrix devices by providing additional releasing surface with time to compensate for the decreasing release rate. The in vitro release of pseudoephedrine hydrochloride as a model compound from the matrices was examined. Modulation of release from a selected matrix containing aminophylline was evaluated in a crossover study using nine beagle dogs. Preliminary in vitro/in vivo correlation was also studied. The systems described in this paper can potentially be scaled up to commercial production.
Qiu
Y
Y
Formulation Development Centre, Pharmaceutical and Analytical R and D, Abbott Laboratories, North Chicago, IL 60064, USA. Yihong.Qiu@abbott.com
Chidambaram
N
N
Flood
K
K
D000628:Aminophylline / Q000493:pharmacokinetics; D000818:Animals; D003692:Delayed-Action Preparations; D004058:Diffusion; D004285:Dogs; D066298:In Vitro Techniques; D008954:Models, Biological; D013499:Surface Properties; D013607:Tablets; D013806:Theophylline / Q000493:pharmacokinetics
D003692:Delayed-Action Preparations; D013607:Tablets; D000628:Aminophylline; D013806:Theophylline