Electrospun polyurethane–eggshell membrane hybrid nanofibrous scaffolds for enhanced fibroblast adhesion and growth in skin tissue engineering

Chronic wounds demand scaffolds that simultaneously deliver mechanical resilience and biological cues to restore fibroblast function and extracellular matrix remodeling. However, it remains unknown how polyurethane–eggshell membrane (PU–ESM) composition quantitatively governs the trade-off between mechanics, physicochemical behavior, and fibroblast responses. Here we establish composition–function relationships in electrospun PU–ESM nanofibrous scaffolds to resolve the optimal balance for skin tissue engineering. Electrospun PU, native and extracted ESM variants, and PU/ESM hybrids (90:10, 80:20, 70:30) were fabricated and evaluated by SEM/EDX/ATR-FTIR, wettability, swelling, degradation, tensile testing, and fibroblast assays (MTT and SEM adhesion; n = 3). ESM incorporation progressively increased hydrophilicity, swelling, and degradation while tuning mechanics (all ANOVA P < 0.001). The 80:20 hybrid achieved a contact angle of 81.56 ± 2.74°, controlled swelling, and intermediate degradation, with stiffness 17.36 ± 0.72 MPa and tensile strength 3.96 ± 0.21 MPa. Fibroblast viability on 80:20 matched controls (P > 0.05) and exceeded pure ESM scaffolds (P < 0.01). SEM quantification revealed previously unresolved gains in cell–scaffold interaction at 80:20, with ~ 2.25-fold higher cell density and ~ 3.8-fold greater cell-covered area versus ePU (P < 0.0001), alongside enhanced spreading. These data demonstrate that a defined PU–ESM ratio (80:20) provides a previously inaccessible balance of mechanics and bioactivity, enabling robust fibroblast adhesion and viability. This framework paves the way for tunable, ECM-mimetic dressings for chronic wound repair.