F. Galisteogonzalez et al., ON THE STRUCTURE OF ELECTRICAL DOUBLE-LAYER OF IGG IMMOBILIZED ON POLYSTYRENE MICROSPHERES, Journal of biomaterials science. Polymer ed., 4(6), 1993, pp. 631-641
Latex particles used in the development of immunoassays usually presen
t stability problems when the antibody is attached to the surface. Thi
s work is an attempt to know the potential distribution parameters aro
und these complexes by electrokinetic measurements. The conversion of
mobility data into zeta-potential was carried out by different theoret
ical approaches developed by Smoluchowski (classical equation), O'Brie
n and White, and Dukhin and Semenikhin. The zeta-potential calculated
with allowance for electrical double layer (e.d.l.) polarization was s
ubstantially greater than zeta calculated according to the classical e
lectrokinetic theory. The greater values of zeta(D-S) in comparison wi
th zeta(O-W) were readily explained on the basis that in the first the
ory, the contribution to polarization from all ions of the diffuse lay
er was taken into account, whereas O'Brien and White accounted for onl
y the ions of the hydrodynamically mobile part of the e.d.l. This is a
n indication that the anomalous surface conductance of latex particles
coated by IgG molecules is much higher than that of bare latex partic
les.