Electrospun core-shell bead-on-string nanofibers for sustained release of simvastatin.

In recent years, nanofibers with core-shell structure as potential drug carriers have been widely explored in biomedical applications, contributing to the controlled release of drug particles. However, smooth core-shell nanofibers may expose large and insoluble drug particles to the fiber surface, causing their sudden release. Therefore, in this paper, in order to fully encapsulate simvastatin (SIM) particles with large size and poor solubility as well as alleviate their sudden release, SIM-loaded bead-on-string nanofibers with core-shell structures (SBNFs) were fabricated using a coaxial electrospinning, in which SIM was encapsulated into the core layer of core-shell beads to enhance its embedding depth. The optimal spinning parameters were determined by studying the morphology, structure, wettability, drug release performance and biocompatibility of SBNFs prepared under different spinning parameters. The results showed that the SBNFs obtained at the optimal parameters had the advantages of both the core-shell structure and beaded structure of drug-loaded nanofibers, which could increase the embedding depth of drugs, thus alleviating the initial sudden release of drugs, achieving the long-term persistent drug release, and ensuring the best biocompatibility with human umbilical vein endothelial cells (ECs). Moreover, the beaded structure of SBNFs could also make ECs have more growth space. This provides a basis for the potential application of bead-on-string nanofibers with core-shell structure in biomedical field. [Display omitted] [ABSTRACT FROM AUTHOR]