Development and Characterization of Gliclazide Solid Dispersion Using Mixed Solvency Concept

Gliclazide, an oral hypoglycaemic drug, has poor aqueous solubility, limiting its oral bioavailability to 50%. This research study aimed to explore the use of mixed solvency techniques to enhance the solubility of a poorly water-soluble drug. The drug was identified and characterized using spectrophotometric analysis, FTIR spectroscopy, and differential scanning calorimetry. The drug was found to be gliclazide, with an aqueous solubility of 0.78 mg/ml. The drug-solubilizers interference study showed no interference in UV spectrophotometric analysis due to excipients. The equilibrium solubility of gliclazide in different solvents was determined using the excess solute method. The highest increase in solubility was found in blend F (30%CP+5%SC+5%SA), but this had a higher concentration of sodium caprylate. Blend Q (10%CP+5%βCD+2.5%SA+2.5%SC) showed a higher increase in solubility, making it suitable for solid dispersion formation. The study concluded that the solubility of gliclazide increases synergistically by mixed solvency. Solid dispersions showed a good drug release profile and were stable at all temperatures and storage conditions.