Fabrication of homogeneously-aligned nano-fillers encapsulated silk fibroin electrospun nanofibers for improved fibroblast attachment, epithelialization, and collagen depositions: in vitro and in vivo wound healing evaluation

Curcumin (CUR), a natural compound found in turmeric that has multiple biological functions such as antibacterial, anti-oxidant, anti-cancer, and wound healing properties due to its hydrophobicity CUR solubilization is a great challenge. In this study, the electrospinning process is used to fabricate a novel active wound dressing based on CUR loaded silk fibroin (SF)/hydroxyapatite (HAp) (SF/HAp-CUR) nanofibers in diabetic rats. The incorporation of CUR into the SF/HAp-CUR nanofibers had an obvious effect on the morphology and dimension of SF/HAp-CUR nanofibers characterized by SEM analysis. Morphological analysis revealed that the average fiber diameter of the SF/HAp, SF/HAp-CUR(1.0%), SF/HAp-CUR(3.0%), and SF/HAp-CUR(5.0%) nanofibers were calculated to be 461 +/- 65 nm, 323 +/- 90 nm, 412 +/- 110, and 497 +/- 118 nm. In addition of CUR in the SF/HAp nanofibers significantly improved the mechanical properties in terms of enhanced elongation at break and tensile strengths. The percentages of water uptake and porosity of SF/HAp-CUR nanofibers were 143.7 +/- 4.05% and 92.5 +/- 3.40%, respectively. The results showed that CUR presented a sustained release behavior from SF/HAp-CUR nanofibers and maintained its free radical scavenging ability. The prepared nanofibers surface interaction was confirmed by FT-IR and XRD analysis. Antibacterial tests revealed SF/HAp-CUR on day 14 improved the bacterial embarrassment of both E. coli and S. aureus by 4 to 5-fold, respectively. The cell cytotoxicity with L929 mouse fibroblasts on the SF/HAp-CUR nanofibers was very low at 7.7 +/- 1.75% on day 14. In vivo wound healing showed that the treatment using SF/HAp-CUR nanofibers significantly increased the rate of wound closure (99.6 +/- 0.86%) on day 21 compared with that using SF/HAp nanofibers (67.7 +/- 4.25%). These results showed that the delivery of SF/HAp-CUR nanofibers can facilitate antibacterial, anti-oxidant, cytotoxicity of wound healing properties.

Automated summary

This study successfully fabricated novel wound dressings based on CUR loaded silk fibroin/hydroxyapatite nanofibers using the electrospinning process. The incorporation of CUR improved the mechanical properties of the nanofibers and facilitated sustained release of CUR, leading to enhanced wound healing, antibacterial, and antioxidant capabilities.