Surface modification of UHMWPE for use in total joint replacements

To create a hydrophilic, lubricious, more wear-resistant UHMWPE bearing, a novel hyaluronan (HA) derivative and novel UHMWPE-hyaluronan composite were developed. HA was silylated to increase its hydrophobicity and compatibility with UHMWPE. The silyl HA rapidly diffused into the connected pores of UHMWPE preforms in xylenes solution, and fixed within UHMWPE and on its surface after crosslinking. A micro-composite was obtained after hot-pressing the porous preform. The presence of HA film on the composite surface has been demonstrated through X-Ray photoelectron spectroscopy (XPS) analysis and Toluidine Blue O (TBO) dye assay. The aqueous contact angles of micro-composite samples were significantly lower compared with UHMWPE control samples, and the samples processed with hydrolysis prior to final molding were superior to those processed with hydrolysis after molding.