In vitro and In vivo Evaluations of Biomimetic Bi-layer Wound Dressing Composed of a Sponge Layer Containing A-PRF and a Nanofiber Layer Containing L-arginine

Platelet-rich fibrin (PRF) has received a great deal of attention in recent years for use in wound treatments due to release of different types of growth factors. The composition of PRF in hydrogels as a wound dressing is a less studied topic. Since monolayer wound dressings may not meet all clinical needs, it is important to design multilayer wound dressings with different characteristics in each layer. In this study, a chitosan/polyethylene glycol (CsPEG) sponge with different percentages (۱, ۱.۵ and ۲% w/v) of advanced platelet-rich fibrin (A-PRF) was prepared as the upper layer of wound dressing, and a Cs/L–arginine electrospun nanofiber layer with different percentages (۰.۲۵, ۰.۵ and ۰.۷۵% w/v) of L-arginine were used as the bottom layer of dressing to mimic the extracellular matrix (ECM) structure. Morphological characteristics and chemical interactions were evaluated using scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR), respectively. Based on the results, the wound dressings contained ۱.۵% of A-PRF had optimal mechanical properties and the presence of nanofiber layer in bi-layer dressings did not have a significant effect on the mechanical properties compared to sponge dressings. In addition, the release of platelet-derived growth factor-AB (PDGF-AB) and vascular endothelial growth factor (VEGF) and the release of L-arginine from the studied wound dressings were investigated. It was shown that the antibacterial activity of Bi-layer۱.۵ dressing against E. coli and S. aureus was significantly higher than other tested dressings due to L-arginine release.

Keywords:

Advanced platelet-rich fibrin , Bi-layer , Chitosan , L-arginine , Nanofiber , Sponge , Wound dressing.