| The solubility of drugs remains one of the most challenging aspects in formulation development. With the advent of combinational chemistry and high throughput screening, the number of poorly water soluble compounds has dramatically increased There are numerous way to improve the solubility of the drug among which solid dispersion is most promising strategy. The aim of the present research work was to make a new generation ternary solid dispersion system of sulfathiazole using different ratio of Drug: Polymer: Surfactant. Different ratios of sulfathiazole: PVP K29/32 : SLS were prepared (1:1:0.1, 1:1:0.5, 1:1:1) and various methods employed to characterize solid dispersion, namely modulated differential scanning calorimeter (MDSC), X-ray powder diffraction (XRPD) and Fourier transformed infrared spectroscopy (FTIR) and dissolution studies. Lack of crystallinity was observed in internal and external systems suggesting loss of crystallinity, while physical mixture showed a characteristic peak of sulfathiazole. In vitro dissolution profiles were generated using different dissolution media. The result dearly shows that the incorporation of relatively small amount (0.1, 0.5 or 1% W/W) of surfactants in to solid dispersion can improve its dissolution rates compare to solid dispersion (SD) and Pure Sulfathiazole. In all ratios SDI (Solid Dispersion Internal) shows higher dissolution rate compare to PM (Physical Mixture) and SDE (Solid Dispersion External). The relative dissolution potency of the three different ratios ranked as 1:1:0.5 > 1:1:1 > 1:1:0.1 for pH 7.4. When water used as dissolution media ratio 1:1:0.5 and 1:1:1 gives the same drug release which is higher than the drug release that we get in case of 1:1:0.1 ternary systems. Solubilization mechanism is responsible for this higher dissolution rate when we incorporate the SLS in Solid Dispersion (SD). |
