Electrospun poly(vinyl alcohol)/hyaluronic acid nanofiber mats for wound care in space: cytocompatibility and effects of UV-C treatment and simulated microgravity.

Electrospun nanofibrous dressings are attractive for wound-care applications in space-related healthcare; however, limited information is available on the stability of UV-C-treated, water-stabilized nanofiber mats after exposure to simulated microgravity and on their cytocompatibility after pre-use treatment. To address this gap, fully aqueous poly(vinyl alcohol) (PVA) and poly (vinyl alcohol)/hyaluronic acid (PVA/HA) electrospun mats were stabilized through citric acid-mediated ester crosslinking and evaluated after UV-C treatment followed by 48 h incubation under static or simulated microgravity conditions. Both x-PVA and x-PVA/HA retained a continuous fibrous architecture without network collapse, although simulated microgravity was associated with formulation-dependent morphological remodeling. x-PVA showed a more pronounced increase in fiber diameter and a coarser network, whereas x-PVA/HA exhibited a more moderate diameter increase while retaining a highly interconnected fibrous organization. Water vapor transmission rates of 2,552.6 ± 66.7 and 2,492.6 ± 21.6 g m-2 day-1 were measured for x-PVA and x-PVA/HA, respectively, indicating substantial vapor transport under the investigated conditions. FTIR-ATR analysis showed preservation of the characteristic bands of the ester-crosslinked PVA-based networks, without evidence of marked chemical degradation. DSC revealed treatment-dependent changes in thermal transitions, whereas simulated microgravity produced no pronounced additional shift compared with the corresponding static controls. In vitro assays performed on UV-C-treated x-PVA/HA supported cytocompatibility across the tested cell models, including human keratinocytes. Overall, citric-acid-crosslinked x-PVA/HA nanofibrous mats combined breathable vapor-regulating behavior with preserved fibrous architecture and physicochemical stability after UV-C treatment and short-term simulated microgravity exposure. Together with the observed in vitro cytocompatibility, these findings support their further investigation as wound-contact materials for space-related healthcare.