1 research outputs found
Interactions of Apolipoproteins AI, AII, B and HDL, LDL, VLDL with Polyurethane and Polyurethane-PEO Surfaces
The lipoproteins
(HDL, LDL, VLDL) are important components of blood
present in high concentration. Surprisingly, their role in blood-biomaterial
interactions has been largely ignored. In previous work apolipoprotein
AI (the main protein component of HDL) was identified as a major constituent
of protein layers adsorbed from plasma to biomaterials having a wide
range of surface properties, and quantitative data on the adsorption
of apo AI to a biomedical grade polyurethane were reported. In the
present communication quantitative data on the adsorption of apo AI,
apo AII and apoB (the latter being a constituent of LDL and VLDL),
as well as the lipoprotein particles themselves (HDL, LDL, VLDL),
to a biomedical segmented polyurethane (PU) with and without an additive
containing polyÂ(ethylene oxide) (material referred to as PEO) are
reported. Using radiolabeled apo AI, apo AII, and apoB, adsorption
levels on PU from buffer at a protein concentration of 50 μg/mL
were found to be 0.34, 0.40, and 0.14 μg/cm<sup>2</sup> (12,
23, and 0.25 nmol/cm<sup>2</sup>) respectively. Adsorption to the
PEO surface was <0.02 μg/cm<sup>2</sup> for all three apolipoproteins
demonstrating the strong protein resistance of this material. In contrast
to the apolipoproteins, significant amounts of the lipoproteins were
found to adsorb to the PEO as well as to the PU surface. X-ray photoelectron
spectra, following exposure of the surfaces to the lipoproteins, showed
a strong phosphorus signal, confirming that adsorption had occurred.
It therefore appears that a PEO-containing surface that is resistant
to apolipoproteins may be less resistant to the corresponding lipoproteins