In vitro complement activation after contact with pyrolytic carbon-coated and uncoated polyethylene terephthalate

This study was undertaken to evaluate whether the pyrolytic carbon coating of polyethylene terephthalate induces complement activation. Complement activation induced by pyrolytic carbon-coated polyethylene terephthalate (PET+PC) in comparison with uncoated polyethylene terephthalate (PET) was assessed on whole blood collected with heparin. The activation of the classic pathway was evaluated by C4d fragment enzyme immunoassay. The activation of the alternative pathway was evaluated with Bb fragment enzyme immunoassay. The results show that uncoated PET activates the alternative pathway, but not the classic one. PET+PC does not induce complement activation, not even through the alternative pathway. Pyrolytic carbon coating therefore contributes to improving blood compatibility.