Table 3.
Method | Examples | Polymers | Properties | Application |
---|---|---|---|---|
Biodegradable porous scaffold: polymeric porous scaffolds with homogenous network | Casting, leaching and foaming methods | PLLA, PLGA, PDLLA, collagen, etc. | Controlled structure & production | Drug delivery, bone & cartilage tissue engineering |
Fibrous scaffolds: mimicking the architecture of natural human tissue at the nanometer scale (Nano, micro & nonwoven fiber) | Electrospinning, self-assembly, & phase separation | PCL, PGA, PLA, PLGA | Biomechanical and biocompatible high surface area | Tissue engineering, drug delivery & wound healing |
Hydrogel scaffold: shape-retentive polymeric network swollen with a high percentage of water | Microfluidics, micromolding, photolithography, & emulsification | PGS, PEG, PDMS, & Silicon PMMA, HA, PEG, Alginate PMMA, PAA, Fibronectin, chitosan Collagen, gelatin & HA | Biological, mechanical, & physical complexity of structure, shape & size | Microdevices, biochips, cell-based microreactors, etc. |
Microsphere scaffold: prepared from a large variety of biodegradable materials, enabling easy control of porosity and pore interconnection | Thermal induction Particle aggregation Solvent evaporation Freezing & drying | PEG, PLLA Chitosan, HAP PLGA & PLAGA Collagen, PLGA, Chitosan | Highly porous for cell transplant Mechanical stability High cellular density Durable & flexible structure | Bone tissue engineering |
Ceramic scaffold: useful due to their similarity to bone mineral & their osteo-conductivity and biocompatibility | Sponge replication Calcium phosphate coating | TCP, BCP, PU sponge, calcium phosphate, PLGA, PS, PP, collagens, silk and hair fibers, etc. | Enhanced biocompatibility and bioreactivity | Bone tissue engineering & orthopedic application |
Functional scaffold: delivering of substances inducing cell growth | Growth factors, hormones and ligands release | Alginate, gelatin, collagens, fibrin, PLGA, PLA, etc. | Variable structure: hydrogels, membranes, microspheres, foams & membranes | Endothelium interaction, tumor vascular interactions, bone regeneration & wound healing |
Acellular scaffold: elimination of the cellular composition without affecting the composition, mechanical integrity and biological activities of the remained ECM | Decellularisation | Biological organs (e.g. lung) | Retain biomechanical properties, anatomical structure & native ECM | Tissue engineering |
“Tissue scaffold”: assist in the production of ECM, and possible integration with in vivo tissue growth | Robotic & automated deposition of cells in 3D space | Tubular collagen gel Sodium alginate | Layers deposition of ECM or cells Multicellular composition reconstituting tissues | Printing 3D organs, acellular polymeric scaffolds & biochips development |
Abbreviations: PLLA, polylactide; PLGA, poly lactic-co-glycolic acid; PDLLA, poly-D,L-lactide; PCL, Polycaprolactone; PGA, polyglycolide; PLA, polylactide; PGS, poly glycerol-sebacate; PEG, Poly ethylene glycol; PDMS, Polydimethylsiloxane; PMMA, polymethyl methacrylate; HA, hyaluronic acid; PAA, Poly acrylic acid; PLAGA, poly-lactide-co-glycolide; TCP, Tricalcium phosphate; BCP, Biphasic Calcium Phosphate; PU, Polyurethane; PS, Polystyrene; PP, Polypropylene