Novel interpenetrating polymer matrix network microparticles for intestinal drug delivery

This paper deals with the synthesis and characterization of Ghatti gum (GG) and chitosan (CS) IPN MP prepared by emulsion-cross-linking method. Glutaraldehyde (GA) was used as a cross-linker. IPN microparticles were used to deliver (DS) Diclofenac sodium (Model anti inflammatory drug) to the intestine. IPN MP were characterized by Scanning electron microscopy (SEM), differential scanning calorimetric (DSC), Fourier Transform Infrared Spectroscopy (FTIR) and evaluated for in vitro dissolution rate. FTIR studies assessed the formation of IPN structure. The surface morphology was studied by SEM. Particle sizes ranged between 294 to 366 μm. After encapsulation into IPN microparticles DSC studies were performed to recognize the crystalline nature of drug. DS percentage encapsulation efficiency (%EE) ranged from 84.09 to 96.81%. Equilibrium swelling was performed in buffer solution (pH 7.4). In-vitro release studies indicated the dependence of drug release rates on both the amount of chitosan and GG used in grounding of microparticles. The release was extended up to 12 hrs and release rates were fitted into an empirical equation to work out the diffusion parameter which indicates a Non-Fickian release. Continuous dissolution-absorption studies were carried out using everted rat intestine for optimized formulation (F9).