Table 2.
Overview of the advantages and the disadvantages of the individual crosslinking methods and the biomaterials that are suitable
| Crosslinking method | Biomaterials | Advantages | Disadvantages | References |
|---|---|---|---|---|
| Physical crosslinking | ||||
| H-bonds | Hyaluronic acid | Naturally formed bonds: cell friendly, thermostable, self-healing | Challenging in synthesis, use of organic solvents | [87, 109] |
| Ionic interactions | Alginate | Fast gelation, high cell viability, reproducibility, thermal induction possible | Complex preparation, limited to electrostatic interactions | [23, 85, 91, 92] |
| Chemical crosslinking | ||||
| Enzymes | Hyaluronic acid | Mild reaction conditions, responsible to environmental changes | Slow crosslinking reaction | [95, 96, 110] |
| Redox reactions | Hyaluronic acid | High stability, simple controlling | Radical formation | [105, 106] |
| Complementary groups | PEG, hyaluronic acid, agarose | High hydrolytic stability | Slow gelation rate | [86, 110, 111] |
| Photo-radiation | Gellan-gum, PEG, hyaluronic acid, collagen | Inducible crosslinking via photo-initiators | UV-light harms microorganisms, optimal conditions highly dependent on materials | [78, 84, 99, 112, 137] |
| Combined crosslinking | Collagen, PEG | Self-healing properties, improved stability, inducible crosslinking, cell protective properties | Dependent on the individual crosslinking methods used | [97, 107, 108] |