A NOVEL APPROACH OF LOCUST BEAN GUM MICROSPHERES FOR COLONIC DELIVERY OF MESALAMINE

Objective: The objective of the present study was to formulate site-specific drug delivery of mesalamine using Locust bean gum.Methods: The core microspheres were prepared by ionic gelation method using CaCl2 solution and cross-linked with glutaraldehyde and were further coated with pH-sensitive polymer eudragit S-100(1.5-4.5 ml) to retard the drug release in the upper gastrointestinal environment (Stomach and small intestine). Microspheres were characterized by ftir spectroscopy, differential scanning calorimetry and evaluated by scanning electron microscopy (SEM), particle size analysis, entrapment efficiency and in vitro drug release studies in different simulated gastric fluids. Stability studies were carried out for one month at 40±2 °C/75±5% RH.Results: The SEM images revealed the surface morphology was rough and smooth for core and coated microspheres, respectively. The optimized batch (ILBG6) of core microspheres(for 7hr), coated microspheres and coated microspheres in presence of rat caecal contents (8%w/v) for 24hr exhibited 98.44±2.48, 73.58±3.49 % and 98.28±4.42 drug release, respectively. The drug release from all locust bean gum microsphere formulations followed higuchi kinetics. Moreover, drug release from Eudragit S-100 coated microspheres followed the korsmeyer-peppas equation with an fickian kinetics mechanism. Finally, stability studies suggested the change in entrapment efficiency and in vitro drug release of microspheres was minimal, indicating good stability of the formulation.Conclusion: The microspheres formed using natural polysaccharide locust beangum by ionic gelation method are capable of colon targeting the anti-inflammatory drug, mesalamine for the treatment of ulcerative colitis.