Cod Fillets Keep Bad Proteins Away

Proteins extracted from Atlantic cod fillets have a remarkable ability to keep metal and plastic surfaces free from gunk. Those antifouling properties could come in handy as nonstick coatings on medical implants, according to Saju Pillai, Ayyoob Arpanaei, and Peter Kingshott of Aarhus University, in Denmark (Biomacromolecules, DOI: 10.1021/bm900589r). Many prosthetic devices are ruined by nonspecific protein adsorption. Stents used to prop open arteries are notoriously prone to fouling by protein adsorption, which can lead to clogged arteries or deadly blood clots. The Aarhus researchers already knew that cod proteins could form a nonstick coating on polystyrene, stainless steel, and glass. But they weren't sure if the substances could repel the sort of human proteins that are the bane of medical devices. Using a quartz crystal microbalance and atomic force microscopy, the team found that a coating from cod effectively prevents the nonspecific adhesion of large, sticky proteins such as fibrinogen and albumin on several materials. The exact composition of the fish protein mixture is not clear, but tropomyosin, muscle troponin, apolipoprotein, and myosin are part of the mix.