Biodegradable Porous Starch Spheres as a Novel Carrier for Enhancement of Dissolution Rate and Oral Bioavailability of Itraconazole

Background: A biodegradable porous starch (BPS) was developed in order to improve dissolution and oral bioavailability of Itraconazole as a poorly water-soluble antifungal drug. Method: BPS was developed by converting native starch from hydrogel to alcogel by solvent exchange method. The developed BPS carrier was characterized by SEM and nitrogen adsorption/desorption analysis to understand surface morphology and porosity distribution respectively. Itraconazole (ITR) was loaded on BPS by adsorption mediated solvent evaporation method, which provides a hydrophilic matrix powder. This causes drug distribution within hydrophilic matrix of porous starch. Results: Solid-state characterization of optimized batch (ITR/BPS-3) was performed using DSC, PXRD, FTIR, SEM and FTIR chemical imaging. In vitro dissolution and in vivo pharmacokinetic studies were performed to evaluate therapeutic potential of ITR/BPS-3 system. In vitro studies of ITR: BPS-3 system revealed a burst effect in drug release (93%) compared to marketed product, which showed 90% drug release at the end of 60 min compared to 84% of marketed. Moreover, ITR/BPS-3 system showed improved oral bioavailability up to 3.93 fold and marketed product shows 3.12 fold compared to ITR. Conclusion: This effect is due to high surface area, improved wettability and reduced crystallinity of ITR due to its adsorption into BPS. A successful methodology was reported to prepare BPS from raw starch.