title: Deposition of complement protein C3b on mixed self-assembled monolayers carrying surface hydroxyl and methyl groups studied by surface plasmon resonance.
abstract: Since complement activation is recognized as a common response of the host defense system when an artificial medical device is applied to a patient, great effort has been devoted to studies on the interaction of the complement system with artificial materials. However, some uncertainties remain, partially because of the lack of well characterized surfaces and suitable analytic methods for study of the surface phenomena that occur on artificial materials under physiologic conditions. In this study, we employed self-assembled monolayers (SAMs) and the surface plasmon resonance (SPR) technique to study interactions of the serum complement with well characterized surfaces. Self-assembled monolayers carrying various concentrations of hydroxyl groups were prepared using 11-mercapto-1-undecanol (C11-OH) and one of n-nonanethiol, n-dodecanethiol, and n-hexadecanethiol. The amount of NHS deposition on the SAMs increased with increasing C11-OH content of the SAMs, and the amount of anti-C3b antibody immobilization formed on the NHS deposition layers increased with increasing C11-OH content of the SAMs. These results clearly demonstrate that a large amount of C3b, produced through the activation of the complement system, binds covalently to and is adsorbed by hydroxyl-group-rich surfaces. The combination of SAMs and the SPR technique is suitable for studying the interaction of the complement system with solid surfaces, and the results should give basic information needed for a rational design of biocompatible surfaces on synthetic materials.
authors.affiliation: Institute for Frontier Medical Sciences, Kyoto University, 53 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto 606-8507, Japan.
authors.forename: Isao
authors.initials: I
authors.lastname: Hirata
authors.forename: Yasunori
authors.initials: Y
authors.lastname: Hioki
authors.forename: Mitsuaki
authors.initials: M
authors.lastname: Toda
authors.forename: Takayuki
authors.initials: T
authors.lastname: Kitazawa
authors.forename: Yoshinobu
authors.initials: Y
authors.lastname: Murakami
authors.forename: Etsuko
authors.initials: E
authors.lastname: Kitano
authors.forename: Hajime
authors.initials: H
authors.lastname: Kitamura
authors.forename: Yoshito
authors.initials: Y
authors.lastname: Ikada
authors.forename: Hiroo
authors.initials: H
authors.lastname: Iwata
mesh_terms: D001323:Autoantibodies / Q000097:blood; D001672:Biocompatible Materials; D001769:Blood; D003179:Complement C3b / Q000276:immunology / Q000378:metabolism*; D006801:Humans; D017550:Spectroscopy, Fourier Transform Infrared; D020349:Surface Plasmon Resonance
chemical_list: D001323:Autoantibodies; D001672:Biocompatible Materials; D003179:Complement C3b