By Manjanna K. M., Shivkumar B., Ashok M. Raichur
Aceclofenac, a novel NSAID used in the treatment of rheumatoid arthritis, frequency of administration may cause certain GI-adverse effects. The objective of the present research work to formulate the aceclofenac sodium microbeads by ionotropic external gelation technique by using sodium alginate and calcium chloride as cross-linking agent. The effects of different variables such as drug-polymer ratios, concentration of cross-linking agent, stirring speed, cross-linking time were evaluated on mean particle size, drug content, swelling properties, drug entrapment efficiency and drug release potential .The shape and surface characteristics were determined by scanning electron microscopy (SEM). While increasing in the concentration of sodium alginate dispersion increased size distribution, flow properties, mean particle size, swelling ratio and drug entrapment efficiency. The mean particle sizes of drug-loaded microbeads were found to be in the range 596.45±1.04 to 880.10±0.13. Increase in the stirring rate and cross-linking time tremendous decrease in mean particle size. The drug entrapment efficiency was obtained in the range of 63.24-98.90%w/v. No significant drug-polymer interactions were observed in FT-IR studies. There is no physical change of the drug in the formulations were observed by differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The release of drug from the microbeads was pH dependent, showed negligible drug release in pH1.2. Under neutral conditions the beads will swell and the drug release depend on swelling and erosion process resulting optimum level of drug released in a sustained manner and exhibited zero-order kinetics and ultimately improves the compliance in the pharmacotherapy of arthritis. The entire process is feasible in an industrial scale and demands pilot study.
Key Words : Sodium alginate, Aceclofenac sodium, pH dependent, Ionotropic external gelation, Sustained release, Zero-order kinetics
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