Chitosan hydrogel covalently crosslinked by gold nanoparticle: Eliminating the use of toxic crosslinkers

Tissue engineering has directed a lot of effort toward the development of devices with suitable biocompatibility and mechanical properties. Chitosan has been pointed as a valuable material to be applied in scaffolds due to its antimicrobial activity and biocompatibility. Nevertheless, the low mechanical resistance associated with the requirement of toxic crosslinkers has hampered translational application of chitosan hydrogel. Herein, the use of gold nanoparticles (AuNP) as crosslinker is reported as a great strategy to obtain chitosan hydrogel without using toxic reactants. In addition, the resultant chitosan hydrogel, crosslinked by AuNP of 30 nm (AuNP30), presented outstanding properties compared to chitosan hydrogel crosslinked by glutaraldehyde. Chitosan hydrogel crosslinked by AuNP30 presented lower porosity, which provided lower swelling degree and slower degradation rate. In addition, compressive strength was about two times higher than the chitosan hydrogel crosslinked by glutaraldehyde. The crosslink by AuNP30 also increased the biocompatibility of the hydrogel. Chitosan hydrogel crosslinked by AuNP30 did not show cytotoxicity against MEF cells, whereas cell viability of cells incubated with extract from chitosan hydrogel crosslinked by glutaraldehyde was only 41%. In conclusion, the results reported herein pointed that the use of AuNP30 as crosslinker agent provided to chitosan hydrogel enhanced properties that made it suitable to application in biomedical devices.

Automated summary

The use of gold nanoparticles (AuNP) as a crosslinker in chitosan hydrogel has been proposed as a superior alternative to traditional methods involving toxic crosslinkers. Chitosan hydrogel crosslinked by AuNP30 exhibited enhanced properties, such as lower porosity, reduced swelling degree, slower degradation rate, increased compressive strength, and improved biocompatibility, making it a promising material for biomedical applications.