Comparative studies of sterilization processes for sensitive medical nano-devices

Abstract

Three-dimensional, open porous sensitive medical devices are increasingly attractive in biomedical engineering; at the same time new challenges immerse since traditional sterilization processes may not be appropriate for use with such sensitive devices. In the present study, we use a lyophilized nanostructured collagen sponge, as a model system of a sensitive medical device in order to study the effects of the two most common sterilization processes. Sterilization with gamma irradiation was found to cause profound effects on the internal structure illustrated by a change of the pore size from ca 70 μm to heterogeneous 40–560 μm. In contrast, ethylene oxide sterilization was seen to largely preserve the interior architecture, although it may alter permanently the surface properties of the sponge. This study helps to highlight the sterilization barriers that this kind of medical devices need to overcome.