Emulsion-electrospun polyvinyl alcohol nanofibers as a solid dispersion system to improve solubility and control the release of probucol, a poorly water-soluble drug

We attempted to improve the solubility of poorly water-soluble drugs by preparing drug-loaded polyvinyl alcohol (PVA) nanofibers as a solid dispersion system via emulsion electrospinning. Probucol (PBC), a poorly water-soluble drug, was used as a model drug. Nanofibers were electrospun using an oil/water (o/w) emulsion consisting of PBC dissolved in an immiscible solvent, such as ethyl acetate, and an aqueous PVA phase. PBC-containing PVA nanofibers with diameters ranging from 300 to 600 nm were obtained by electrospinning from o/w emulsions. The physical properties of the nanofibers were affected by the degrees of polymerization and hydrolysis of the PVA grades. In PVA nanofibers prepared without a surfactant, PBC existed in an amorphous state, and the dissolution of PBC was greatly improved. PBC dissolution was lower in PVA nanofibers with 30% PBC content compared to those with 11% or 20% PBC. In PVA nanofibers prepared using the surfactant polysorbate 80 as an emulsifier, PBC was partially crystallized; however, the PBC was homogenously dispersed, and dissolution was improved, even in PVA nanofibers containing 30% PBC. PVA nanofibers produced by o/w emulsion electrospinning were demonstrated to be suitable solid dispersion systems enabling robust controlled release of poorly water-soluble drugs.