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The aim of the work was to enhance the dissolution rate of rivaroxaban by preparing its solid dispersions (SDs) using hydrophilic carrier poloxamer 188. The prepared solid dispersions were characterized by Fourier-transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). Both solubility and dissolution rate of the drug in these formulations were increased. The SDs of rivaroxaban with poloxamer 188 were prepared at 1:1, 1:2 and 1:3 w/w ratios by physical mixing, melting and solvent evaporation techniques. The used hydrophilic carrier showed more than two fold increase in dissolution rate in their prepared solid dispersions by melting or solvent evaporation techniques. The FTIR spectroscopic and DCS thermal studies showed the compatibility of rivaroxaban and absence of well-defined drug polymer interactions, though shift in peaks observed due to formation of new bonds.

Objective: The aim of the work was to enhance the dissolution rate of rivaroxaban by preparing its solid dispersions (SDs) using hydrophilic carrier PEG 4000. Methods: The SDs of rivaroxaban with PEG 4000 were prepared at 1:1, 1:2 and 1:3 w/w ratios by physical mixing, melting and solvent evaporation techniques. The prepared solid dispersions were characterized by Fourier-transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). Results: Both the solubility and dissolution rate of the drug in these formulations were increased. The used hydrophilic carriers showed a more than two-fold increase in dissolution rate in their prepared solid dispersions by melting or solvent evaporation techniques. The pure drug rivaroxaban as the pure drug shows a dissolution rate of nearly 39 % after 60 m, whereas the solid dispersions by melting or solvent evaporation showed 90% of dissolution after 60 m. The FTIR spectroscopic and DCS thermal studies showed the compatibility of rivaroxaban and the absence of well-defined drug polymer interactions, though the shift in peaks was observed due to the formation of new bonds. Conclusion: Formulation of solid dispersions of drug with hydrophilic carriers is a successful approach for solubility or dissolution rate enhancement of low soluble drug(s). In this work for solubility enhancement of rivaroxaban the hydrophilic carrier PEG 4000 showed significant solubility enhancement.

Objective: The aim of the proposed study was formulation and in vitro/ vivo evolution   of solid dispersions of glipizide with gum Aegle marmelos. Methods: The phase solubility of glipizide in 0.1N HCl was investigated in the presence of different concentrations of gum Aegle marmelos. The solid dispersions (SDs) of glipizide with gum Aegle marmelos were formulated using solvent evaporation method at ratios of 1:1, 1:2, and 1:5 (glipizide: gum Aegle marmelos). Dissolution studies were conducted. The physicochemical characterization of the formulations was performed by using Fourier-transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC) and X-ray diffraction (XRD). Subsequently, bioavailability of pure glipizide, solid dispersion and marketed product was performed in rat. Results: Glipizide solubility increased as the concentration of gum Aegle marmelos in 0.1N HCl was raised. The solubility study indicates spontaneous drug solubilization, which is supported by negative values of Gibb's free energy (ΔGotr). Glipizide rate of dissolution was increased in SDs containing gum, and the rate increased as the concentration of gum in the SDs increases. After preparing SDs and physical mixtures with gum, the mean dissolution time (MDT) of glipizide decreases considerably. FTIR spectroscopy study revealed that stability and the absence of a well-defined glipizide-gum interaction. The amorphous condition of glipizide in SDs of glipizide with gum was revealed by DSC and XRD studies. Conclusion: The DSC and XRD studies indicate conversion of drug from crystalline to microcrystalline or amorphous form after formulation of solid dispersion with Aegle gum. The solid dispersion of glipizide with Aegle gum (893.04±25.5) showed better therapeutic activity compared to pure glipizide (535.65±11.5) and marketed formulation (767.5±13.6).

The aim of this study was to make and characterize Glipizide solid dispersions utilizing a low viscosity grade of hydoxypropyl methyl cellulose (HPMCLV). The phase solubility character of Glipizide in presence of various concentrations of HPMCLV in 0.1N HCl was evaluated. Glipizide solubility increases as the concentration of HPMC in 0.1N HCl was increased. Gibbs free energy (ΔGotr) values were all negative, indicating that drug solubilization occurs spontaneously. Solid dispersions of Glipizide with HPMCLV were prepared by using solvent evaporation method The physical properties of Glipizide with HPMCLV SDs were investigated using Fourier-transform infrared (FTIR) spectroscopy, differential scanning calorimetry (DSC), and X-ray diffraction (XRD). Dissolution studies was also performed. Subsequently, bioavailability of pure Glipizide, solid dispersion and marketed product was performed. Glipizide dissolution rate was enhanced in SDs containing HPMC, and the rate increased as the concentration of HPMC in the SDs increase. After preparing SDs and a physical mixture with HPMC, the mean dissolving time (MDT) of Glipizide decreased significantly. FTIR spectroscopy tests revealed Glipizide's stability and the absence of a well-defined Glipizide-HPMCLV interaction. The amorphous condition of Glipizide in SDs of Glipizide with HPMCLV was revealed by DSC and XRD studies. When compared to pure drug and marketed product, solid dispersion of Glipizide with HPMCLV exhibited improved bioavailability.