The antimicrobial effect of calcium-doped titanium is activated by fibrinogen adsorption
Huiliang Cao, Thomas J. Dauben, Christian Helbing, Zhichao Jia, Yuechao Zhang, Moran Huang, Lenka Müller, Song Gu, Xiaoyuan Zhang, Hui Qin, Karin Martin, Jörg Bossert, Klaus D. Jandt
Abstract
, ATCC 27853) while presenting strong inhibition efficiency on bacterial colonization after fibrinogen adsorption onto the material. Fine X-ray photoelectron spectroscopy and Fourier-transform infrared spectroscopy analyses reported calcium-dependent shifts of the binding energy in nitrogen and oxygen involved groups and wavenumbers in the amide I and II bands of the adsorbent fibrinogen, demonstrating that locally delivered calcium can react with the carboxy-terminal regions of the Aα chains and influence their interaction with the N-termini of the Bβ chains in fibrinogen. These reactions facilitate the exposure of the antimicrobial motifs of the protein, indicating the reason for the surprising antimicrobial efficacy of calcium-doped titanium. Since protein adsorption is an immediate intrinsic step during the implantation surgery, this finding may shift the present paradigm on the design of implantable antibacterial biomaterial surfaces.