A Cytocompatible Hydrogel Through Metal Coordinate And Covalent Crosslinking

In the field of microscale tissue engineering and biomedical implant material,hydrogel were biocompatible materials for extensive using.The structure of hydrogel,a three dimensional network and higher water content,is similar to humans’extracellular matrix（ECM）environment.Making control of hydrogel properties,such as mechanical stiffness,antibacterial property and hemolysis property,will enlarge the application range of hydrogel.Double network hydrogel integrated two independent crosslinking network together,a type of hard brittle network structure and another type of the soft tenacity network structure.By adjusting the ratio of those two can achieve the aim of balancing hardness and toughness.When introducing function groups to structure the dual network to improve hydrogels’mechanical properties,it will make the materials more functional.Histidine,an amino acid that is often involved in metal ion coordination in proteins,is hypothesized to bind metal ions such as Zn²⁺and Cu²⁺in the byssal thread,whereupon the metal coordination bond is thought to break under applied load,serving as an energy dissipating mechanism.It is often seen as benign antibacterial agent in the field of antibacterial material.Herein,imidazole functional group was firstly introduced into the hydrogels’covalent bond primary network.Secondly,physical network cross-linked through imidazole-zinc ion coordination bonds.Therefore,a high strength and antibacterial zinc ion coordinated dual network structure hydrogels of imidazole/gelatin methylacrylic（GelMA）was obtained.The results showed that zinc ion coordinated imidazole/GelMA dual network structure hydrogels’strength property has been significantly improved because of the coordination bonds/covalent bond dual network.And the prepared zinc ion coordinated imidazole/GelMA dual network hydrogels have a high antibacterial ratio about99.9%comparing against the GelMA hydrogrels’none antibacterial property.It is great that the prepared zinc ion coordinated imidazole/GelMA dual network hydrogels still remain the excellent biocompatibility and blood compatibility.It has potential applications in biomedical materials and tissue engineering.The combination of metal ions with the imidazole group,which inhibits the signal pathway of the tumor cells,will form a biohydrogel that effectively inhibits the growth of tumor cells...