Enhanced solubility and dissolution rate of itraconazole by a solid dispersion technique

Abstract

The aim of the present study was to improve the solubility and dissolution rate of a poorly water-soluble drug, itraconazole, by a solid dispersion technique. Solid dispersion particles of itraconazole were prepared with various pH-independent and -dependent hydrophilic polymers and were characterized by differential scanning calorimetry, powder X-ray diffraction and scanning electron microscopy. Of the polymers tested, pH-dependent hydrophilic polymers, AEA® and Eudragit® E 100, resulted in highest increases in drug solubility (range, 141.4–146.9-fold increases). The shape of the solid dispersion particles was spherical, with their internal diameter ranging from 1–10 μm. The dissolution rate of itraconazole from the tablets prepared by spray drying (SD-T) was fast, with >90% released within 5 min. SD-T prepared with AEA® or Eudragit® E 100 at a 1:1 drug to hydrophilic polymer ratio (w/w) showed approximately 70-fold increases in the dissolution rate over a marketed product.