Biotribological application of poly(ε-caprolactone)-poly(ethylene glycol)-poly(ε-caprolactone) hydrogel as an efficient carrier with slow-release lubrication effect

Excessive wear debris in prosthesis tends to induce loosening, which is a major problem affecting the durability of long-serving implants. Although bionic synovial fluid can be used to improve the lubrication of artificial joints, the fluid is often absorbed easily by the tissues of human body. To enhance the effectiveness of bionic synovial fluid, poly(ε-caprolactone)-poly(ethylene glycol)-poly(ε-caprolactone) (PCEC) hydrogel was prepared as a carrier for the bovine serum albumin (BSA) in synovial fluid. It thus significantly reduces the loss rate of BSA. Experimental results show that the good sustainability and favorable release ability of hydrogel efficiently prevent the rapid outflowing of BSA. Experiments also reveal that the PCEC hydrogel inclines to form a particular structure with BSA and thus give BSA an excellent slow-release performance. Furthermore, friction and wear tests indicate that the released solution from the PCEC hydrogel possesses good lubricating properties. In general, the average friction coefficient of released solution is approximatively 77% lower than that of the normal phosphate-buffered solution. This study furnishes with an effective approach to prolong the lubricating duration of BSA in artificial prostheses.