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

Abstract

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.