Biocompatibility vs antibacterial activity: chitosan-mediated nanosilver/PCL/gelatin nanofibers

Abstract

Electrospinning is an efficient approach to prepare nanofiber scaffolds that mimic local tissue environments. While many reported scaffolds incorporate nanoparticles, detailed assessments of how nanosilver distribution affects antibacterial activity and biocompatibility remain limited. In this study, we developed an electrospun biopolymer scaffold composed of polycaprolactone and gelatin with chitosan-mediated nanosilver (C-AgNPs), introduced either by bulk surface coating or by dispersing the NPs within the electrospinning solution. The C-AgNP surface-coated scaffold exhibited antibacterial activity against Staphylococcus aureus and Escherichia coli, whereas the dispersed scaffold did not. However, the dispersed scaffold promoted higher dermal fibroblast viability (82.7%) compared with the coated scaffold (60.9%). Zebrafish embryo assays further revealed mild developmental toxicity from the coated scaffold but no observable toxicity from the dispersed formulation. These findings demonstrate a distinct trade-off between antibacterial efficacy and cytocompatibility depending on nanoparticle distribution. Understanding this relationship is critical for designing electrospun nanofiber scaffolds with balanced biological properties.