Table 4.
Scaffold manufacturing strategies and relative applications in NTE.
| Strategies | Preparation method | Advantages | Disadvantages | Application | Ref. |
|---|---|---|---|---|---|
| Freeze-drying | Polymers dissolved in a specific solvent | 1. Ease of operation 2. Maintenance of bioactivity without temperature elevation 3. Tunable porosity |
1. High energy cost 2. Endurable experimental duration 3. Compromised surface topology |
1. Repair of particular brain trauma 2. Collagen-based SCI repair 3. Nerve grafts in peripheral nerves |
[116] |
| Electrospinning | Solution of natural or synthetic polymers | 1. Efficacy in preparing micro-/nana-scales fibrous mesh 2. High porosity and surface area to volume ratio 3. Precise control of fibre alignment 4. Convenient post-processing |
1. Requirement of the high voltage field 2. Potential toxicity of the solvent |
1. Guidance for directional migration of NSCs 2. Sheet rolling process for fabricating nerve conduits in PNS repair |
[117] |
| Extrusion-based bioprinting | Cells encapsulated in homogenous, viscoelastic bioink | 1. Combination of multiple types of cells, bioink, and growth factors involved in 3D milieu 2. Customized size control |
1. Limited bioprinting resolution (about 100 μm) | 1. In vivo neural analysis 2. SCI repair |
[118,119] |
| Inkjet bioprinting | Dispersion of low-viscous droplets in a controllable manner | 1. High printing speed (1–10,000 droplets per second) 2. High resolution (50 μm) |
1. Low cell density (<106 cells/ml) | 1. Fabrication of functional neural constructs | [120,121] |
| Stereolithography | Biodegradable, biocompatible polymers | 1. 3D architectural integrity 2. High accuracy and resolution (25 μm) 3. No cost of possibly fabricating waste |
1. Resins with cytotoxic residues 2. Costly specialized equipment |
1. SCI repair | [122] |