Biomimetic PLGA nanofiber scaffolds: Crystallization-driven mechanical reinforcement and degradation kinetics...

Balancing mechanical fatigue resistance with precise degradation kinetics remains a pivotal challenge in the engineering of biodegradable polymeric scaffolds. Herein, we fabricated biomimetic tubular scaffolds via sequential electrospinning, systematically modulating the physicochemical properties of poly(lactic-co-glycolic acid) (PLGA) by tailoring the lactide/glycolide monomer ratios. By optimizing the sacrificial layer protocol and collector rotation speed, a defect-free nanofibrous network mimicking the natural extracellular matrix (ECM) was constructed. Structural characterization using XRD and DSC revealed that optimizing the lactide content to a 7:3 ratio triggered a critical phase transition from an amorphous to a semi-crystalline state. This crystallization-driven microstructural evolution endowed the scaffold with superior radial compression resilience and effectively recapitulated the "fiber-bridging" toughening mechanism of natural lotus stems. Degradation kinetics analysis in artificial urine demonstrated that the semi-crystalline scaffold exhibited a diffusion-limited bulk erosion profile with mitigated autocatalysis, maintaining mechanical integrity for over four weeks. Furthermore, the optimized surface wettability and topological cues significantly fostered fibroblast adhesion and proliferation. Collectively, this study elucidates the structure-property relationships of electrospun PLGA nanofibers, offering a robust strategy for designing mechanically durable and degradation-tunable biomaterials.