This study reports the development and characterization of hierarchical electrospun scaffolds based on poly (L-lactic acid) (PLA) and polyacrylonitrile (PAN) reinforced with calcium oxide (CaO) nanoparticles (18.5 ± 4.7 nm) for skin regeneration. Six configurations, including two five-layer multilayer systems (PLA/PAN/CaO and PAN/PLA/CaO), were evaluated to determine how composition and deposition sequence influence physicochemical, mechanical, and biological performance. FT-IR, XRD and DSC confirmed the successful integration of CaO, while thermal analysis evidenced an effect of chain mobility and interfacial interactions within multilayer systems. Cross-sectional SEM revealed the presence of both fibers with continuous interfaces. Nitrogen adsorption showed that CaO significantly increased the specific surface area (e.g., from 4.6 m²/g in neat PLA to 21.65 m²/g in PLA/CaO), with type IV isotherms indicating mesoporosity. Wettability assays demonstrated reduced contact angle in PLA (from 126.3° to 91.8°) and sequence-dependent surface properties in multilayers. Tensile testing confirmed that the multilayer architecture bridged the mechanical gap between compliant PLA and high-strength PAN, yielding intermediate moduli (~10–11 MPa) and balanced toughness. Antibacterial assays against S. aureus and E. coli showed that CaO significantly reduced bacterial viability, with PLA/PAN/CaO achieving the highest inhibition (up to 37.1%). In vitro HaCaT assays and in vivo implantation in BALB/c mice confirmed high cytocompatibility and biocompatibility. These findings demonstrate that multilayer electrospinning of PLA/PAN/CaO enables the design of structurally integrated, bioactive, and mechanically balanced scaffolds for advanced wound healing and dermal repair.

Multifunctional polymer scaffolds with mechanical support, biocompatibility, and antimicrobial activity are key for next-generation biomedical materials. We report the fabrication of electrospun nanocomposite fibers made from polycaprolactone (PCL), starch, and mesoporous aluminum oxide nanoparticles (n-Al₂O₃). Nanoparticles (11 ± 4 nm) were synthesized via a sol-gel method, predominantly comprising γ- and α-Al₂O₃ phases. Four fiber systems were fabricated by side-by-side electrospinning: PCL, PCL/starch, PCL/n-Al₂O₃, and PCL/starch/n-Al₂O₃. SEM analysis confirmed uniform and bead-free fibers in all formulations. Tensile tests showed that the incorporation of starch and nanoparticles improved the mechanical performance compared with neat PCL. In particular, PCL/starch/n-Al₂O₃ fibers exhibited increases of 404% in Young’s modulus and 102% in elongation at break. In PBS, starch and n-Al₂O₃ enhanced hydrophilicity and accelerated weight loss, with PCL/starch/n-Al₂O₃ showing the highest mass loss. Antibacterial tests indicated that only fibers with nanoparticles could inhibit Staphylococcus aureus and Escherichia coli, with PCL/starch/n-Al₂O₃ showing a major effect. Although n-Al₂O₃ increased cytotoxicity toward NIH-3T3, starch mitigated this effect, and the ternary scaffold showed no detectable cytotoxicity. Moreover, PCL/starch/n-Al₂O₃ exhibited non-hemolytic behavior, enhanced fibroblast migration, and wound-healing-related protein expression. Overall, side-by-side electrospun PCL/starch/n-Al₂O₃ scaffold exhibited showed improved mechanical, biological, and antibacterial properties, supporting its potential as a wound-dressing material.

This study presents an innovative approach for the synthesis of a mesoporous silica material derived from fly ash and functionalized with glycine (S2E-G) for the adsorption of rare earth elements (Dy3+ and Lu3+), underscoring a circular economy and sustainability approach. The resulting SBA-15 type mesoestructure exhibited a specific surface area of 403 m2 g-1 and an average pore diameter of 16.3 nm. Functionalization was confirmed by FTIR, CHNS, and XPS analyses, showing a grafting efficiency of 82%. Adsorption tests demonstrated exceptionally fast kinetics, with 90% capture of Lu3+ and 80% of Dy3+ achieved in just 5 minutes. The material exhibited a significant maximum adsorption capacity for Lu3+ (45.3 mg g-1), positioning it as promising given the scarcity of silica-based adsorbents for this element. Kinetic and isotherm modeling, along with density functional theory (DFT) simulation, confirmed that chemisorption is the dominant mechanism, mediated by the strong coordination between REE ions and the amino/carboxyl groups of glycine.These findings highlight the potential of fly ash reuse in developing sustainable mesoporous adsorbents for critical metal recovery, circular economy applications, and environmental remediation.