ABSTRACT:
The microspheres were prepared by ionic cross-linking technique. Chemical reaction between sodium alginate and calcium chloride to form calcium alginate was utilized for microspheres. For slowing the rate of release from microspheres the hydrophilic polymer Locust bean gum and xanthan gum and their combinations was added in different concentration so that the drug will be release constantly for 12hrs. The formulation prepared showed the angle of repose within acceptable range having a good flow property. The drug entrapment efficacy of all the formulation was in the range of 90.6 – 98.9%. The drug entrapment efficacy of microspheres increases with increase in concentration of hydrophilic gums. Diclofenac sodium in vitro release from microspheres was studied. The microspheres containing 2.5% of Locust bean gum: xanthan gum (6:4) shows 98.8% drug release. The values of co-efficient correlation (r) were calculated and were found to be linear for first order release as compare to zero order release. Scanning electron microscopy of selected formulation indicated that the microspheres are spherical in shape and smooth surface. Stability studies reveled that polymers used were stable and compatible with the drug and there is no significant effect on physical characteristics, drug content and dissolution profile of the microsphere.