Formulation and Evaluation of Diclofenac Sodium Matrix Tablets Based on Tamarindus indica Seed Mucilage

In the present investigation, tamarind seed mucilage was evaluated as sustained release matrix forming material in Diclofenac sodium tablet formulations. The physicochemical properties, tamarind seed mucilage such as loss on drying, viscosity, swelling index, pH and melting point were studied. Matrix tablets were prepared by wet granulation technique using isopropyl alcohol as a granulating agent. Sustained release matrix tablets of diclofenac sodium, were developed by using different drug: polymer ratios, such as AF1 (1:0.5), AF2 (1:1), AF3 (1:1.5), AF4 (1:2) and AF5 (1:2.5). All the lubricated formulations were compressed using flat faced punches. Compressed tablets were evaluated for uniformity of weight, content of active ingredient, friability, hardness, thickness, in vitro dissolution using paddle method, and swelling behavior. All the formulations showed compliance with pharmacopoeial standards. Tablets prepared with Hydroxypropylmethylcellulose (HPMC 50cps) and Xanthan gum as matrix forming material for the comparative study. Among different formulations, AF2 showed sustained release of drug for 12 hours with 92.75% release. The dissolution profiles of the HPMC (GF1) and Xanthan gum (FF1) based matrix tablets were close to the profile obtained by tamarind seed mucilage based matrix tablets AF2. The kinetic treatment showed that the release of drug follows zero order model and anomalous diffusion for AF2 and FF1 while the drug release of GF1 was best explained by Higuchi's model and anomalous diffusion. The selected formulation (AF2) was subjected to stability studies for three months at 45° temperature with RH 75±5%, and showed stability with respect to release pattern. It is cleared that the drug release from matrix tablets prepared by using tamarind gum can be sustained for more than 12 hrs and release of drug vary with concentration of polymer in matrix tablets.