Azithromycin-Laden Core-Shell Polycaprolactone/Gelatin Fibers for Disinfection and Regeneration

Objectives: Core-shell fibers serve as controlled drug delivery systems, where the regulation of polymer degradation is critical for precise drug release from the shell and core exposure at the appropriate time. This study aimed to synthesize, characterize, and assess the cytocompatibility of Polycaprolactone (PCL)/Gelatin core-shell fibers, using two distinct crosslinking methods and incorporated with azithromycin (AZ).
Methods: Electrospinning was employed to fabricate the core-shell fibers, which were crosslinked using two distinct methods: Glutaraldehyde Vapor and EDC (1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride) solution, while uncrosslinked samples were maintained as control. The efficacy of the crosslinking methods was ascertained through morphological evaluation (SEM, n=3), degradation (n=6) as determined by FTIR analysis (n=3) over a 3-week period to confirm the presence of gelatin (Shell), and cell viability (n=5) of alveolar bone-derived mesenchymal stem cells (aBMSCs). The crosslinking method exhibiting optimal properties was selected for use in scaffolds incorporated with AZ. Concentrations of AZ (5% and 15%; w/w) were loaded into the shell and assessed for cell viability (n=6). Data were subjected to ANOVA and post-hoc analyses (α=5%).
Results: The core-shell fibers were effectively visualized using scanning electron microscopy (SEM). The degradation assay and FTIR revealed that the utilization of EDC was more effective in reducing the degradation rate of gelatin for up to 3 weeks. Furthermore, the cell viability assay revealed no significant difference between the crosslinking methods (p<0.999). The EDC method was selected to be used on the AZ-loaded scaffolds. The concentrations of AZ incorporated didn’t affect fiber morphology, according to the SEM findings. Meanwhile, cell viability was not affected even by the highest concentration of AZ incorporated over the evaluated time points (p≥0.8451).
Conclusions: EDC can modulate the degradation of core-shell fibrous scaffolds maintaining cytocompatibility, and AZ-loaded core-shell fibers hold potential as an approach for tissue engineering and controlled antibiotic delivery.