A self-healing bio-lubricating hydrogel coating synergistically enhanced with ZIF-8 nanoparticles, exhibiting corrosion resistance, antibacterial properties, and wear resistance

Hydrogel is an ideal material for replacing natural articular cartilage. However, their inadequate mechanical properties, such as severe dynamic damage, restrict their application in the field of joint replacement. Herein, on the basis of Schiff base bonds (dialdehyde starch (DS) with acrylamide (AM)) and metal coordination bonds (Fe³⁺ with DS), we designed a self-healing bio-lubricant hydrogel coating (DS/AM/Fe³⁺). Moreover, a nanocomposite metal-organic framework (ZIF-8) was applied to the DS/AM/Fe³⁺ hydrogels to improve their mechanical properties. The 1,000 ppm ZIF-8/DS/AM/Fe³⁺ hydrogel coatings exhibit excellent tribological properties and corrosion resistance, with a 32.94% reduction in the wear rate, a coefficient of friction of 0.104, and a corrosion inhibition efficiency of up to 79.63%, as well as active antibacterial and biological activity. The designed hydrogel has potential applications for artificial joint replacement.