Improving dissolution profile of poorly water-soluble drug using non-ordered mesoporous silica

The aim of the study was to increase dissolution rate of atorvastatin by the use of mesoporous silica SYLOID® 244 FP. The poorly soluble drug atorvastatin was adsorbed on and/or into SYLOID® 244 FP in the ratios 1:1, 1:1.1.5, 1:2, 1:2.5, 1:3 and 1:3.5 via a wetness impregnation method. The absence of crystalline form and presence of hydrogen bond interaction between atorvastatin and SYLOID® 244 FP is done by Fourier-transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC). The atorvastatin loaded matrix lacked in the crystalline form of atorvastatin and it showed improvement in the dissolution rate of ATC. The flowability of the atorvastatin loaded matrix powder was evaluated by bulk density, Carr’s index and angle of repose. This matrix was then processed into a tablet by direct compression method. A 3² full factorial design was applied to investigate the combined effect of two formulation variables - volume of ethanol and amount of SYLOID® 244 FP. The tablets were evaluated for hardness, friability, drug content and drug dissolution studies. The solubility of atorvastatin-loaded matrix was increased up to 4.28 times. Atorvastatin tablet prepared from drug-loaded silica may provide a feasible approach for development of an oral formulation for this poorly water-soluble drug.