Bergstrand Anna, Rahmani-Monfared Ghazal, Ostlund Asa, Nydén Magnus, Holmberg Krister
Department of Chemical and Biological Engineering, Applied Surface Chemistry, Chalmers University of Technology, SE-412 96 Göteborg, Sweden.
J Biomed Mater Res A. 2009 Mar 1;88(3):608-15. doi: 10.1002/jbm.a.31894.
The effect of surface charge on the protein resistance of adsorbed layers of poly(ethylene imine)-[g]-poly(ethylene glycol), PEI-PEG, and poly(L-lysine)-[g]-poly(ethylene glycol), PLL-PEG, was studied. Mixed and monofunctional self-assembled monolayers, SAMs, on gold were obtained by adsorption of 16-mercapto-1-hexadecanoic acid and 16-mercapto-1-hexadecanol. The surface charge was systematically varied by changing the ratio of the two alkanethiols. The graft copolymers PEI-PEG and PLL-PEG were adsorbed at the SAMs and tested for resistance towards human serum albumin and fibrinogen. The adsorbed amount of copolymers increased with increasing negative surface charge. However, the best protein resistance was found at an intermediate surface charge. The PLL-PEG covered surfaces showed better protein resistance than the PEI-PEG covered surfaces. Thus, this work demonstrates that an adsorbed layer of PEG-grafted PEI and, in particular, PEG-grafted PLL is efficient in preventing protein adsorption when there is charge neutralization between the copolymer and the underlying surface.
研究了表面电荷对聚（乙烯亚胺）-[接枝]-聚（乙二醇）（PEI-PEG）和聚（L-赖氨酸）-[接枝]-聚（乙二醇）（PLL-PEG）吸附层蛋白质抗性的影响。通过吸附16-巯基-1-十六烷酸和16-巯基-1-十六醇，在金表面获得了混合和单官能团自组装单分子层（SAMs）。通过改变两种烷硫醇的比例来系统地改变表面电荷。将接枝共聚物PEI-PEG和PLL-PEG吸附在SAMs上，并测试其对人血清白蛋白和纤维蛋白原的抗性。共聚物的吸附量随着表面负电荷的增加而增加。然而，在中等表面电荷时发现了最佳的蛋白质抗性。PLL-PEG覆盖的表面比PEI-PEG覆盖的表面表现出更好的蛋白质抗性。因此，这项工作表明，当共聚物与下层表面之间存在电荷中和时，PEG接枝的PEI，特别是PEG接枝的PLL的吸附层在防止蛋白质吸附方面是有效的。
