Enhanced stability and solubility of pH-dependent drug, telmisartan achieved by solid dispersion

The aim of this study was to enhance the dissolution rate and stability of telmisartan (TLM), a poorly water-soluble drug by using solid dispersion (SD) technique. TLM-SD was prepared by a melting and solvent evaporation method. The solubility test was performed in pH 7.5 buffer and distilled water (DW), and dissolution test in buffer solutions of pH 1.2, 6.8, and 7.5. The stability of TLM-SD was evaluated by hygroscopicity, drug content, and dissolution rate. The physical properties were evaluated using field emission scanning electron microscopy (FE-SEM), differential scanning calorimetry (DSC), Fourier transform infrared (FT-IR), and powder X-ray diffraction (PXRD). Hydrogen bonds were formed between TLM and alkalizer surface on a colloidal silicon dioxide (Aerosil 200) as a carrier in the prepared SD. Solubilizer and alkalizer were screened; PVP K30 and meglumine were selected via solubility test. The dissolution rate of the optimized TLM-SD tablet significantly increased by 2.6-and 1.6-fold in comparison with physical mixture and commercial products in pH 7.5 buffer at 15 min, respectively. Moreover, TLM-SD tablet was more stable than commercial products in 40 degrees C/75% RH. In conclusion, the in vitro dissolution rate and stability of TLM-SD tablets were successfully improved compared to commercial products (Micardis (R)). (C) 2017 Elsevier B.V. All rights reserved.