Physicochemical Characterization of Solid Dispersion of Telmisartan with Alkaliser by Hot Melt Method

The effect of molecular weight of polyethylene glycols (PEGS) and drug/PEG ratio on the structure and dissolution rates of the solid dispersions with Telmisartan have been examined. Telmisartan (TEL) was chosen as a model drug due to its poor and pH dependent water solubility. The alkalizer used to modify the pH of TEL was NaOH, in the SD system significantly increased the drug dissolution rate in gastric fluid (pH 1.2) . Structural change in drug crystallinity to an amorphous form was also a contributing factor based on differential scanning calorimetry (DSC) thermograms and powder X-ray diffraction (PXRD) patterns. The drug frequency of the C=O band decreased and the O–H broad band in the Fourier transform infrared (FTIR) spectra disappeared when this alkalizer was added. It was evident that the alkalizer in PEG 6000 based SDs synergistically enhanced dissolution of TEL not only by modulating pH but also by changing drug crystallinity to an amorphous form via molecular interactions.