Alginate | It exhibits cytocompatibility and does not exert a toxic effect on encapsulated cells. It can be used at a wide range of concentrations for bioprinting applications. It facilitates immunological isolation of encapsulated cells. It can readily be crosslinked using divalent cations.
| | [110, 111] |
Gelatin | It consists of cell adhesion RGD motifs. It is biocompatible, and can promote cellular proliferation and synthesis of ECM. It possesses thermoresponsive sol-gel transition behaviour facilitating printability. It is biodegradable and can be cleaved by MMP’s thereby facilitating cell migration. It can easily undergo chemical modifications (e.g., methacrylation) to increase its versatility in bioink development.
| It exhibits weak mechanical properties at physiological temperatures. It has poor resolution of bioprinted structures when printed alone, thereby requiring blending with other polymers or crosslinking.
| [112, 113] |
pdECM | It retains the natural microenvironmental components of the physiological residence of islets. It naturally provides cell attachment sites and biomolecular and biomolecular cues to support cell growth and viability.
| | [114, 115] |
Hyaluronic acid | It is biocompatible and biodegradable. It has highly tunable mechanical and degradation properties. It can be easily subjected to chemical modifications and cross-linking that would enable better printability and stability.
| It cannot be utilised in its pure form for bioink development since it lacks printability and is unstable due to its high-water absorption. It rapidly gets absorbed in vivo. Hence chemical crosslinking is necessary.
| [116, 117] |
PLA | It is FDA approved for biomedical applications. Its physico-chemical properties can be tuned as per requirement. It has a long half-life and, therefore extensively used in the fabrication of long-term implantable scaffolds.
| | [118, 119] |
PCL | It is biocompatible, biodegradable, and FDA approved. It has remarkable blend compatibility and versatile viscoelastic properties. It has tunable mechanical and degradation properties.
| | [120] |