Author(s): Ramalingam Nethaji1* , Anjali Narayanan1, Manikandan Palanivelu1, N. Subramaniam Surendiran1 and Babu Ganesan2
Metformin Hcl is a biguanide antidiabetic agent which is used in the management of type 2 diabetes and it is preferably absorbed in the upper part of the GIT and readily soluble in gastric pH of the stomach. The present study, Metformin Hcl was formulated to develop gastro retentive formulation using sodium alginate and different concentration of natural mucoadhesive polymers such as xanthan gum and guar gum by ionic gelation technique with an aim to controlled release and improve bioavailability. Six formulations were prepared by using different drug to polymer ratios, were evaluated for relevant parameters. Depending upon the drug to polymer ratios, the percentage yield is found between 78.06±0.51% to 89.35±0.83% in all formulations. The entrapment efficiency of prepared microspheres was in the range of 83.60±0.71% to 97.16±0.53%. Microspheres showed a good specificity, spherical in shape and the mean particle size of microspheres significantly increase with increasing polymer concentration and it was in the range between 22.42±0.12µm to 30.12±0.41µm. Swelling Index of the mucoadhesive microspheres was in the range of 66.37± 0.07% to 55.07± 0.05%. In-vitro drug release studies was performed in simulated gastric fluid, it is revealed that formulation code XG-III was 94.96±0.16% and GG-III was 92.98±0.22% drug releases at the end of dissolution studies respectively, when compared to all batches due to increases in polymer concentration. Stability studies of selected Metformin Hcl mucoadhesive microspheres showed good results. It could be also concluding that the all the formulations were shown satisfactory results and suitable for potential therapeutic uses.