关键词: 生物医用纺织材料, 取向纳米纤维膜, 静电纺丝, 神经向分化, 周围神经损伤, 壳聚糖, 聚己内酯

Abstract:

Objective In order to address the lack of in-depth investigation into the relationship among electrospinning parameters, nanofiber morphology, and cell behavior, this study systematically investigates the influence of key electrospinning parameters on the morphological structure of chitosan/polycaprolactone (CS/PCL) nanofiber membranes and evaluates the physical guidance effect of the oriented nanofiber membrane on bone marrow mesenchymal stem cells (MSCs), providing fundamental theoretical support for the design of neural tissue engineering scaffolds.

Method CS/PCL nanofiber membranes were prepared via electrospinning. The influence of key parameters (receiving distance, outflow velocity, receiving roller speed) on membrane morphology was investigated to screen optimal fabrication conditions. The biocompatibility of the nanofiber membranes was evaluated using CCK-8 and live/dead assays, and the physical guidance effect on MSCs was assessed by observing cell adhesion, morphology, and alignment on the oriented nanofiber membranes via immunofluorescence staining and gradient dehydration followed by scanning electron microscopy observation.

Results The optimization of electrospinning parameters revealed that the synergistic effect between receiving distance and outflow velocity is crucial for obtaining uniform fibers. Under a receiving distance of 16 cm and an outflow velocity of 0.8 mL/h, nanofibers with an average diameter of 274 nm and uniform morphology were successfully prepared. Meanwhile, the receiving roller speed was found to be the key parameter for regulating fiber orientation. As the receiving roller speed increased from 1 500 r/min to 2 500 r/min, the fiber orientation degree demonstrated significant improvement. However, when the receiving roller speed was further increased to 3 000 r/min, excessive mechanical stress caused disorder in fiber alignment, resulting in a decrease in orientation degree. The resulting CS/PCL nanofiber membranes exhibited good biocompatibility and had a certain promoting effect on the proliferation of MSCs. More importantly, cells on the highly oriented nanofiber membrane adhered well and aligned along the oriented direction of the fibers, exhibiting a pronounced directional extension behavior. Furthermore, cells displayed an elongated morphology closely resembling that of neuronal axons, indicating that the oriented nanofiber membrane has the potential to promote neural differentiation of MSCs.

Conclusion This study successfully fabricated highly oriented CS/PCL nanofiber membrane with excellent morphological characteristics through systematic optimization of electrospinning parameters. In vitro cell experiments demonstrated that this highly ordered physical structure exerts a significant physical guidance effect on bone marrow mesenchymal stem cells. Specifically, the oriented nanofiber membrane not only effectively promoted cell adhesion and alignment along the fiber orientation direction but also induced cells to exhibit a neuron-like morphology. This finding confirms that the oriented nanofiber membrane can regulate stem cell behavior and differentiation through physical signals, providing solid experimental evidence for the design of neural tissue engineering scaffolds based on physical structure regulation.

Key words: biomedical textile material, oriented nanofiber membrane, electrospinning, neuronal differentiation, peripheral nerve injury, chitosan, polycaprolactone