INFLUENCE OF NATURAL GUMS FOR EFFECTIVE COLON TARGETING OF METHOTREXATE FOR THE TREATMENT OF COLORECTAL CANCER

Bharani S. Sogali, Mohammed Yousuff and Shashank Nayak

Colon-specific drug delivery systems (CDDS) are developed to reduce side effects and to achieve high local drug concentration at the affected site in the colon, hence optimal therapeutic effectiveness and good patient compliance. The aim of the present investigation was to develop colon targeted drug delivery system for methotrexate using guar gum and pectin as a carriers in the treatment of crohn’s disease, ulcerative colitis, colorectal cancer, etc. Fast-disintegrating methotrexate core tablets were compression-coated with different ratios of guar gum and pectin. All the formulations were evaluated for the hardness, drug content uniformity, and subjected to in vitro drug release studies with and without rat caecal contents. The in vitro studies concluded that, amongst the different formulations, the F10 containing polymers 50%(guar gum and pectin) in the ratio 1:1 showed better drug release and satisfactory results showing a release of 83.4±0.98% of methotrexate after degradation by colonic bacteria at the end of 24 hrs of the dissolution study and 49.4±0.9% in simulated colonic fluids. The statistical significance was tested by using Student’s t-test and found statistically significant. Optimised F10 formulation was subjected to stability studies at 40ºC±2ºC/75%±5% RH for 3 months and observed no significant change either in physical appearance, drug content or dissolution pattern. The DSC study showed that methotrexate did not react with polymers (guar gum & pectin) or other excipients used in the study.