Hydroxypropylmethylcellulose-Carboxypolymer matrix tablets for the controlled release of Sodium Diclofenac: Formulation and in vitro characterization.

BRAVO S.; LAMAS, M.C.; SALOMON C.J.

Conferencia; VI Pharmatech-International Conference on Pharmaceutics and Pharmaceutical Technology; 2001

Over the last two decades extensive research has been performed in the design and development of sustained release systems. Hydrophilic matrix tablets for the sustained drug release, contain a therapeutic agent dispersed in a compressed water-swellable polymeric core.1 In recent years hydrophilic cellulose derivatives have become the most widely used polymers for novel drug delivery systems. One of the most popular hydrosoluble polymers used in controlled release dosage forms is hydroxypropylmethylcellulose (HPMC).2 On the other hand, carboxypolymer (Carbopol 934) is a high molecular weight, cross-linked polymer of acrylic acid co-polymerized with polyalkylsucrose. The final product contains many carboxylic acid groups. The hydrogel presents high viscosity characteristics being influenced by pH changes and presence of electrolytes.3 Diclofenac Sodium was selected as a model drug in the formulation of sustained release HPMC-carbopol matrix tablet