Solubility improvement of curcumin by crystallization inhibition from polymeric surfactants in amorphous solid dispersions

To improve the solubility and maintain amorphous state of curcumin (CUR), solid dispersions of CUR with Kollidon CLSF and surfactant (TPGS or HPMC) were prepared by solvent evaporated method. The solid dispersions were characterized by scanning electron microscope, powder X-ray diffraction, differential scanning calorimetry and fourier transform infrared spectroscopy. The solubilization mechanism of surfactants in vitro and the pharmaceutical properties of optimal formulations in vivo were studied. The results showed that TPGS as a carrier provided superior solubility and stability for SDs due to its stable hydrogen bonding strength and related crystal nuclei growth mechanism. At different pH conditions (pH 1.2 and 6.8), TPGS significantly improved the solubility and release rate of CUR in solid dispersions. Thus, solid dispersion with high solubility and stability significantly enhanced the oral bioavailability and gastric ulcer healing rate. Therefore, solid dispersion with novel applied surfactants is an effect strategy to improve pharmaceutical properties of CUR.