Green-synthesized MXenes enable low-friction, cytocompatible PVA-chitosan hydrogels

Area of Science:

• Biomaterials Science
• Materials Chemistry
• Nanotechnology

Background:

• Developing soft, hydrated biomaterials for cartilage interfaces requires balancing high hydration, low friction, and cytocompatibility.
• Existing hydrogel systems face challenges in simultaneously achieving these critical properties.

Purpose of the Study:

• To create novel poly(vinyl alcohol)-chitosan (PVA-CS) hydrogels reinforced with green-synthesized Ti3C2Tx MXene flakes.
• To evaluate the cytocompatibility, hydration, mechanical properties, and tribological performance of these enhanced hydrogels.

Main Methods:

• Utilized a mild, HF-free synthesis for O-terminated, multilayered Ti3C2Tx MXene flakes.
• Incorporated MXenes into a PVA-CS polymer network, followed by a sodium-citrate salting-out process.
• Assessed hydrogel properties including swelling, water content, mechanical response, cytocompatibility (fibroblast and chondrocyte viability), and friction.

Main Results:

• MXene reinforcement increased equilibrium swelling and maintained high water content (>89%).
• Enhanced compressive and viscoelastic properties were observed with MXene addition.
• Hydrogels demonstrated excellent cytocompatibility, supporting both fibroblast and chondrocyte viability.
• A significant reduction in friction (~15% vs. PVA-CS, ~70-80% vs. titanium alloy) was achieved.

Conclusions:

• Green MXene-reinforced PVA-CS hydrogels are safe, highly hydrated, and exhibit low-friction characteristics.
• These biomaterials show significant potential for cartilage-related and other load-bearing interfaces.
• The developed hydrogels offer a promising solution for applications demanding reduced friction and biocompatibility.