Graphene oxide/poly(ethylene glycol)/chitosan gel with slow-release lubrication applied on textured surface

Graphene oxide/poly(ethylene glycol) (GO/PEG) composites that have biocompatibility and biodegradability properties have been prepared to improve the lubrication of artificial joints, but they would be rapidly degraded and absorbed by the human body if injected. To prolong the lubrication effect, GO/PEG lubricants were mixed into a chitosan (CS) sol, and then the GO/PEG/CS sol was added to the dimpled texture of a Co-Cr-Mo alloy and transformed into a gel to slowly release GO/PEG lubricants. The results of friction experiments showed that the average friction coefficient of the slow-release solution is below 0.025, especially when under pressure, and the gel in the texture also has a good lubrication effect. Meanwhile, the FTIR and UV–vis of the slow-release solution indicated that it is likely to contain GO, PEG, and CS, which are associated with each other via hydrogen bonds and may form a particular structure, leading to good slow-release lubrication.