ABSTRACT The interaction of proteins with solid surfaces is a fundamental phenomenon in the biomaterials field. We investigated, using atomic force microscopy (AFM), the interactions of a recombinant amelogenin with titanium, a biphasic calcium phosphate (BCP) and mica. The unbinding processes were compared to those of an earlier studied protein, namely fibrinogen. Force spectroscopy (AFM) experiments were carried out at 0 ms, 102 ms, 103 ms and 104 ms of contact time. In general, the rupture forces increased as a function of interaction time. The unbinding forces of amelogenin interacting with the BCP surface were always stronger than those of the amelogenin-titanium system. The unbinding forces of fibrinogen interacting with the BCP surface were always much stronger than those of the fibrinogen-titanium system. For the most part, this study provides direct evidence that recombinant amelogenin binds more strongly than fibrinogen on the studied substrates.
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nullL. Richert, A. Boukari, S. Berner, M. Dard and J. Hemmerlé, "Unbinding Process of Amelogenin and Fibrinogen Adsorbed on Different Solid Surfaces Using AFM," Journal of Biomaterials and Nanobiotechnology, Vol. 2 No. 3, 2011, pp. 244-249. doi: 10.4236/jbnb.2011.23031.
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