a method for producing increased resistance to biodegradability is provided for biomedical devices subject to in vivo implantation . among the steps required to produce such resistance are the application of a thermoplastic polyurethane coating to the device to provide a coating , and the subsequent crosslinking of the thermoplastic polyurethane coating through the application of radiation of a sufficient intensity and duration to convert said thermoplastic polyurethane coating to a thermoset coating possessing the attribute of increased biostability .