C. Godin et A. Caprani, INTERACTIONS OF ERYTHROCYTES WITH AN ARTIFICIAL WALL - INFLUENCE OF THE ELECTRICAL SURFACE-CHARGE, European biophysics journal, 25(1), 1996, pp. 25-30
Electrical charge on any biological surface plays a crucial role in it
s interaction with other molecules or surfaces. Here, we study, under
flow conditions, the interactions of erythrocyte. with an artificial s
urface: a platinum microelectrode whose charge density ranges from -15
to +27 mu C/cm(2). This artificial surface could be similar in surfac
e charge to an endothelium or a biomaterial. In this model, interactio
ns are measured as a transient relative increase of the electrolyte re
sistance obtained by impedance measurement of a microelectrode. A maxi
mal interaction of erythrocytes viith the charged surface is calculate
d in the 0 to +10 mu C/cm(2) charge density range. At negative surface
charge, a less efficient contact was obtained because of electrostati
c repulsion forces. High positive surface charge (charge density >10 m
u C/cm(2)) does not improve the contact but induces a progressive decr
ease in the contact efficiency, which could be explained by a re arran
gement of macromolecules on the erythrocyte surface or an effect of po
sitive groups on the cell membrane. This work suggests that a greater
surface area of contact is obtained in the 0 to +10 mu C/cm(2) charge
density range and that this is provided by more molecular bridges.