Novel multi-layer silica aerogel/PVA composite for controlled drug delivery

A novel multi-layer composite (MLC) was developed consisting of a polyvinyl alcohol (PVA) film as a substrate and a drug loaded silica aerogel powder which coated by PVA nano fibers. It was tested as a controlled drug delivery system (DDS) with fluconazole as an anti-fungal drug. The hydrophilic and hydrophobic silica aerogels synthesized at ambient pressure and loaded with the fluconazole. Results of drug release showed that silica aerogels have a faster release rather than pure fluconazole because of a high specific surface area (>800 m² g⁻¹) and high porosity (>80%). Release rate of about 80% of the fluconazole loaded in the hydrophilic and hydrophobic silica aerogels showed an increase of 3.7-fold and 2.5-fold compare to the crystalline form of the drug, respectively. Furthermore, the PVA nano fibers help to control the fluconazole release rate. The silica aerogel/PVA composites exhibited the non-Fickian mechanism for the drug release while, the loaded silica aerogel powders follow the Fickian mechanism. The composite contains hydrophilic silica aerogel showed stronger effect on the controlled drug release compare to the hydrophobic sample. The results of the anti-fungal properties showed that the drug loaded samples have a good consequence on the fungal. (paper)