Acetylated yeast mannan endowing biomimetic electrospun nanofibers with hydrophobicity and moisturizing property for accelerated cutaneous defects repair.

Mammalian skin is composed of hydrophobic polymers such as proteins, polysaccharide and oily matrices, serving as a crucial barrier to prevent adverse factors from rapidly infiltrating the body while also functioning as a key organ for material exchange. However, open wounds resulting from skin defects can disrupt the internal stability of the body's environment, leading to water loss and delaying the wound healing process. Mannan is believed to synergize with natural moisturizing factors (NMF). Inspired by the hydrophobic structure of skin, firstly, acetylated yeast mannans (AM) were synthetized as a hydrophobic and moisturizing component. Subsequently, we developed a composite electrospun nanofiber (PVCQAM), which integrates polyvinyl alcohol (PVA, a biocompatible component), AM, collagen (Col, extracellular matrix component), and quaternized chitosan (QCS, a hydrophobic and antibacterial component) to the mimic the architecture and functions involved in wound healing. AM enhanced the surface hydrophobicity compared to the mannan-containing nanofibers (PVCQM). Furthermore, as the degree of acetylation increased, nanofibers manifested improved hydrophobic properties. The nanofibers demonstrated thermal stability, and suitable stretchability that aligns with human tissue characteristics. The incorporation of QCS imparted inherent antibacterial effects to the biomimetic nanofibers against S. aureus and E. coli. Notably, excellent cytocompatibility and hemocompatibility in vitro have prompted us to evaluate the therapeutic efficacy in a cutaneous defect model. The electrospun nanofibers in this study displayed significant anti-inflammatory effects and promoted collagen deposition, resulting in an impressive wound closure rate of 95 %. The skin-inspired nanofiber dressing based on hydrophobic AM presents significant potential for moisturizing and facilitating benign tissue repair in defect management.