Preliminary investigations of banana (Musa paradisiaca) starch mucilage as binder in metformin tablet formulation.

The binding properties of banana (Musa paradisiaca) starchwas investigated using maize starch BP and polyvinylpyrrolidone (PVP) as standards in the formulation of metformin tablets. Starch from unripe banana fruits was extracted with distilled water. Mucilages of the banana and maize starches and solutions of PVP at 5 and 10 %w/v were used to produce metformin granules by wet granulation and compressed into tablets. Granules and tablets properties were evaluated. Compatibility studies using differential scanning calorimetry (DSC) and Fourier transform infrared spectroscopy (FTIR) were also carried out. Granules flow properties was of the order: PVP>banana starch > maize starch. DSC and FTIR analysis reveals no interaction between excipients and metformin. Increase in concentration of banana starch mucilage from 5-10% w/v led to an increase in hardness, disintegration time and decrease in friability of the tablets. Tablets of banana starch mucilages were comparable in tablet properties with those of maize starch mucilages and PVP solutions with no significant differences (p<0.05). The tablets exhibited crushing strength, friability and disintegration time values ranging from 6.75-12.00 kp, 0.82-1.50 % and 11.04-14.51 min, respectively. The tablet parameters met compendial requirements at binder concentrations studied except friability values for tablets of PVP. Results revealed that banana starch could be used as a binding agent in metformin tablet formulation due to its comparable binding property with maize starch BP and PVP.