Plasma-based sterilization: Effect on surface and bulk properties and hydrolytic stability of reprocessed polyurethane electrophysiology catheters

Plasma-based sterilization is a promising alternative to ethylene oxide (EO ) for reprocessing of electrophysiology catheters. To assess its safety in terms of material damage, modifications of surface and bulk properties as w ell as hydrolytic stability of sterilized catheters were evaluated. Polyure thane (PU) single-use electrophysiology catheters were subjected to one, fi ve, and ten sterilization cycles by Sterrad-100S(R) and Plazlyte(TM), as we ll as by pure EO for comparison. Surface analysis techniques (ATR-FTIR, XPS , DCA) showed oxidation Limited to the near-surface layer induced by both p lasma-based sterilizers, whereas EO induced slight but deeper alkylation. U sing bulk analysis techniques (RP-HPLC, SEC), oligomer alteration was obser ved after all three sterilization techniques, without modification of molec ular weights. Hydrolytic stability of catheters was slightly changed by pla sma-based sterilization, with a small increase in released oligomers. Final ly, although Plazlyte and Sterrad are both plasma-based techniques, they in duced different impacts on catheters, such as the degradation of an additiv e with Sterrad, and a clear difference in coloration with Plazlyte. (C) 200 0 John Wiley & Sons, Inc.