Emulsion electrospun epigallocatechin gallate-loaded silk fibroin/polycaprolactone nanofibrous membranes for enhancing guided bone regeneration

Guided bone regeneration (GBR) membranes play an important role in oral bone regeneration. However, enhancing their bone regeneration potential and antibacterial properties is crucial. Herein, silk fibroin (SF)/polycaprolactone (PCL) core-shell nanofibers loaded with epigallocatechin gallate (EGCG) were prepared using emulsion electrospinning. The nanofibrous membranes were characterized via scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, thermogravimetric analysis, water contact angle (CA) measurement, mechanical properties testing, drug release kinetics, and 1,1-diphenyl-2-picryl-hydrazyl radical (DPPH) free radical scavenging assay. Mouse pre-osteoblast MC3T3-E1 cells were used to assess the biological characteristics, cytocompatibility, and osteogenic differentiation potential of the nanofibrous membrane. Additionally, the antibacterial properties against<i>Staphylococcus aureus (S. aureus)</i>and<i>Escherichia coli (E. coli)</i>were evaluated. The nanofibers prepared by emulsion electrospinning exhibited a stable core-shell structure with a smooth and continuous surface. The tensile strength of the SF/PCL membrane loaded with EGCG was 3.88 ± 0.15 Mpa, the water CA was 50°, and the DPPH clearance rate at 24 h was 81.73% ± 0.07%. The EGCG release rate of membranes prepared by emulsion electrospinning was reduced by 12% within 72 h compared to that of membranes prepared via traditional electrospinning.<i>In vitro</i>experiments indicate that the core-shell membranes loaded with EGCG demonstrated good cell compatibility and promoted adhesion, proliferation, and osteogenic differentiation of MC3T3-E1 cells. Furthermore, the EGCG-loaded membranes exhibited inhibitory effects on<i>E. coli</i>and<i>S. aureus</i>. These findings indicate that core-shell nanofibrous membranes encapsulated with EGCG prepared using emulsion electrospinning possess good antioxidant, osteogenic, and antibacterial properties, making them potential candidates for research in GBR materials.