3D printed poly(lactic acid)/poly(ε-caprolactone)/graphene nanocomposite scaffolds for peripheral nerve tissue engineering

This research aimed to fabricate and evaluate Poly(lactic acid)/poly(ε-caprolactone)/graphene (PLA/PCL/G) nanocomposite scaffolds for peripheral nerve tissue engineering. To achieve this goal, scaffolds were fabricated using the fused deposition modeling (FDM) 3D printing method with the following compositions: 50 wt% PLA-50 wt% PCL (PLA-PCL), 98.5 wt% PLA-1.5 wt% G (PLA-G), 98.5 wt% PCL-1.5 wt% G (PCL-G), and 50 wt% PLA-48.5 wt% PCL-1.5 wt% G (PLA-PCL-G). The microstructure and chemical composition of the scaffolds were characterized using SEM, XRD, and FTIR. SEM images revealed that the PLA-PCL-G scaffold exhibited a more regular and uniform morphology compared to the others, with the PLA-PCL scaffold displaying the least regularity. The porosity percentage and pore size of the scaffolds ranged from 50 % to 86 % and 300 to 500 µm, respectively. Mechanical properties were assessed via compression testing, indicating that the elastic modulus of the PLA-PCL-G scaffold was approximately 22.36 MPa, suitable for peripheral nerve tissue applications. Electrical conductivity testing showed that PLA-PCL-G had a conductivity of about 8.2E-5 S/cm, similar to PLA-G. Biodegradability was evaluated by immersing samples in phosphate-buffered saline (PBS), revealing that PLA-PCL-G exhibited a weight loss of approximately 1.3 % and a degradation rate of 0.14 mm/day over four weeks, closely matching peripheral nerve tissue regeneration rates. MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay results confirmed that PLA-PCL-G scaffolds were non-cytotoxic to PC12 cells. Overall, these findings suggest that the 50 wt% PLA-48.5 wt% PCL-1.5 wt% G scaffold holds promise for peripheral nerve tissue engineering applications.