Biomedical Engineering Reference
In-Depth Information
6
Studying molecular-scale protein-surface
interactions in biomaterials
P. S. SIT, Louisiana Tech University, USA
DOI
: 10.1533/9780857093684.182
Abstract
: Protein interactions with implant surface are an integral part
of a series of events that could determine the outcome of the implant
devices. Atomic force microscopy (AFM), when operates under fl uid
conditions, allows proteins to maintain their natural functionality. AFM
provides important information regarding the interfacial properties of
fi brinogen, such as molecular conformations in three dimensions, and
corresponding functionalities, temporal and temperature-dependent
adsorption profi le and adhesion strength. It has been demonstrated
that the structure-function relationship of fi brinogen is a function
of the physio-chemical properties of the underlying substrates. The
operation capability of AFM can be further improved by increasing
temporal resolution, increasing the resemblance to natural physiological
environment and distinguishing among different proteins during
competitive adsorption on the biomaterial surface.
Key words
: atomic force microscopy, fi brinogen, protein-surface
interactions, adsorption profi le, protein conformation, protein function,
intermolecular interactions.
6.1
Introduction: surface-induced thrombosis on
artificial surfaces
Surface-induced thrombosis involves complex interactions between various
components of the blood, notably platelets and plasma proteins with arti-
fi cial (e.g. polymeric implantable biomaterials) or natural (e.g. atheroscle-
rotic lesions) surfaces.
1,2
For biomaterial scientists and clinical physicians,
the inevitable protein adsorption and the subsequent thrombus formation
remain a major obstacle to the improvement of blood biocompatibility and
hence the long-term use and safety of cardiovascular implant devices. A
good understanding of this subject has a profound infl uence on the design
of materials for either the promotion or avoidance of protein adsorption.
Unfortunately, the detailed mechanisms are still largely not understood.
182
