FORMULATION AND EVALUATION OF INTERPENETRATING POLYMER NETWORK MICROSPHERES OF INDOMETHACIN BY IONOTROPIC GELATION METHOD

Abstract

The objective of this research was to formulate interpenetrating polymer network microspheres of indomethacin using sodium alginate and carboxymethyl Delonix regia gum by ionotropic gelation method. Calcium chloride was used in formulations F1 to F4, while calcium chloride along with glutaraldehyde was used in formulations F5 to F8 as a crosslinking agent. Microspheres were characterized by scanning electron microscopy, differential scanning calorimetry and X-ray diffraction studies. The percentage of drug entrapment increased with an increase in the total concentration of polymers. The sizes of microspheres were in the range of 47.2 to 59.5 µm. In vitro dissolution study showed a decrease in the rate of drug release with an increase in the concentration of carboxymethyl Delonix regia gum. Formulations containing glutaraldehyde showed a decrease in the rate of drug release with an increase in the concentration of glutaraldehyde from 2 to 5 % w/v. For all formulations of prepared microspheres, the values of n varied within 0.680 to 0.888, indicated anomalous type diffusive transport.