Formulation and evaluation of microspheres of anti-inflammatory drug diacerein prepared by ionotropic gelation method

Abstract

The context of this research was to reduce the untoward effects of diacerein by preparing a microsphere formulation of the same. The ionotropic gelation method was adopted to prepare diacerein microspheres. This method involves the interaction of two ionic components under certain conditions. Among these two ionic components, at least one component must be a polymer. Simple interaction between ionic polymer with oppositely charged ion leads to the formation of microspheres. In this process, sodium alginate and Chitosan were used as polymers, whereas for the crosslinking process, calcium chloride was used. The prepared formulations of diacerein displayed mean particle size ranging from 106-542 µm, while the percentage yield ranged from 49-82. An increased concentration of calcium chloride and sodium alginate increases the particle size. However, an increased chitosan concentration was found to increase the drug entrapment efficiency of the microspheres. Further, phosphate buffer media (pH 6.8) in the USP paddle type dissolution apparatus were used for the percentage drug release study. Results showed that increased chitosan concentration slows the release of drugs from microspheres. We noted that the B3 formulation, which contains sodium alginate: Chitosan (1:3), showed the lowermost rate of drug release. Besides, SEM studies of the same formulation (B3) revealed that microspheres have spherical shapes with rough surfaces. It was observed that the B3 formulation showed a significant result in formulation evaluation studies; hence, it may be further considered an optimized formulation for preclinical evaluation