Development and evaluation of carbomer based matrices for the controlled delivery of diclofenac sodium

Abstract

Diclofenac Sodium (DS) is a potent non-steroidal anti-inflammatory drug used in treatment of osteoarthritis, rheumatoid arthritis and ankylosing spondylitis. An investigation was carried out to develop sustained and controlled release carbomer matrices of DS using Carbopol 974P alone as well as in combinations with Hydroxypropylmethylcellulose (HPMC) and Carboxymethylcellulose (CMC) and to evaluate them for physical characteristics like thickness, weight variation, hardness, drug content uniformity and drug delivery performance. The in vitro study was carried out in pH 7.4 buffer medium (Simulated Intestinal Fluid) using USP XXI dissolution apparatus II. The kinetics of release data were evaluated using regression coefficient analysis and mechanism of release by Peppas exponential equation, Mt / M∞ = Ktn. The observation of results clearly indicated that carbomer matrices of DS provided greater control over drug delivery for longer duration and followed non-Fickian diffusion mechanism, with zero order release kinetics.