Development of Polyvinyl Alcohol (PVA) Nanofibers Containing Cationic Lipid/siRNA Complexes via Electrospinning: The Impact of PVA Characterization

This study aimed to develop polyvinyl alcohol (PVA) nanofibers encapsulating 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP)/siRNA complexes via electrospinning for the delivery of nucleic acid-based drugs. It also focused on the influence of the intrinsic properties of PVA on the efficacy of the system. PVA nanofibers, with diameters of 300–400 nm, were obtained, within which the siRNA remained intact and the DOTAP/siRNA complexes were uniformly dispersed. By incorporating DOTAP/siRNA complexes into the PVA nanofibers and assessing the impact of their RNA interference (RNAi) activity in A549-Luc cells, a stable inhibition of luciferase expression was observed. An examination of the nanofiber preparation process revealed that even when DOTAP or siRNA were added separately to the PVA solution without forming complexes, the RNAi effect was retained. The DOTAP/siRNA complexes released from the PVA nanofibers were internalized by the cells, with some PVA residues remaining on their surfaces. The significance of the degree of hydrolysis and polymerization of PVA on the performance of nanofibers was highlighted. Notably, PVA with a low degree of hydrolysis substantially enhanced RNAi effects, with luciferase expression inhibition reaching 91.5 ± 0.7%. Nanofibers made of PVA grades with anionic or cationic modifications were also evaluated, suggesting that they affect the efficacy of siRNA delivery. The insights obtained suggest avenues for future research to optimize drug delivery systems further.