Title:Mechanisms of Fibrinogen Adsorption at Solid Substrates
VOLUME: 14 ISSUE: 6
Author(s):Zbigniew Adamczyk, Anna Bratek-Skicki, Paulina Zeliszewska and Monika Wasilewska
Affiliation:J. Haber Institute of Catalysis and Surface Chemistry, Polish Academy of Sciences, Niezapominajek 8, 30- 239 Cracow, Poland.
Keywords:Adsorption of fibrinogen, conformations of fibrinogen in electrolyte solutions, electrophoretic mobility and charge
of fibrinogen molecule, fibrinogen adsorption mechanisms, fibrinogen molecule shape and size, interactions of bioparticles
with fibrinogen monolayers, monolayers of fibrinogen on solid substrates.
Abstract:The aim of this work was to critically review recent results pertinent to fibrinogen adsorption at
solid/electrolyte interfaces with the emphasis focused on a quantitative analysis of these processes in terms of the electrostatic
interactions. Accordingly, in the first part, the primary chemical structure of fibrinogen is analyzed. Physicochemical
data pertinent to the bulk properties derived from hydrodynamic, dynamic light scattering and micro-electrophoretic
measurements aided by theoretical modeling are discussed. Possible conformations and the effective charge distribution
over the fibrinogen molecule for various pH an ionic strength are defined, especially the semi-collapsed conformation
prevailing at physiological conditions. Adsorption kinetics of fibrinogen at hydrophilic and hydrophobic (polymer modified)
substrates determined by various techniques is described. Adsorption at polymeric carrier particles, pertinent to immunological
assays, studied in terms of electrokinetic and concentration depletion methods, are also considered. The reversibility
of adsorption, fibrinogen molecule orientations and maximum coverages are thoroughly discussed. The stability
of fibrinogen monolayers formed at these carrier particles in respect to pH and ionic strength cyclic changes is also
discussed. In the final section interactions and deposition of model colloid particles on fibrinogen monolayers are analyzed
which allows one to derive valuable information about molecule orientations. Based on the physicochemical data,
adsorption kinetics and colloid particle deposition measurements, probable adsorption mechanisms of fibrinogen on
solid/electrolyte interfaces are defined.
