Hemmersam Anne Gry, Rechendorff Kristian, Foss Morten, Sutherland Duncan S, Besenbacher Flemming
Interdisciplinary Nanoscience Center and Department of Physics and Astronomy, University of Aarhus, 8000 Aarhus C, Denmark.
J Colloid Interface Sci. 2008 Apr 1;320(1):110-6. doi: 10.1016/j.jcis.2007.11.047. Epub 2007 Dec 7.
The adsorption of fibronectin on gold, Ti-, and Ta-oxide surfaces is investigated by means of the quartz crystal microbalance with dissipation (QCM-D) technique. The surface chemistry (gold, Ti-, and Ta-oxide) is found to influence the frequency shift observed during adsorption of the fibronectin layer with the magnitude being Delta f Au>Delta f Ti-oxide approximately Delta f Ta-oxide. Corresponding variations in the dissipation change normalised to frequency change (Delta D/Delta f) for the layer are observed. The QCM-D data are further analyzed by the random sequential adsorption (RSA) model, and adsorption rate parameter ka and footprint (a) determined, which supported the trend seen in the Delta f and Delta D/Delta f values. The value of ka found by the RSA modelling of the QCM-D resonance frequency data is found to match the ratio between the mass measured by QCM-D and the mass reported by optical techniques in literature. We conclude that comparison of the adsorption rate parameter (ka) obtained by RSA modelling of the QCM-D data with ka values obtained from RSA modelling of data obtained using optical techniques can be a route to determine the degree of hydration of the adsorbed protein layer.
采用带耗散监测的石英晶体微天平（QCM-D）技术，研究了纤连蛋白在金、氧化钛和氧化钽表面的吸附情况。研究发现，表面化学性质（金、氧化钛和氧化钽）会影响纤连蛋白层吸附过程中观察到的频率变化，其幅度为Δf Au>Δf 氧化钛≈Δf 氧化钽。同时观察到该层的耗散变化相对于频率变化（ΔD/Δf）的相应变化。通过随机顺序吸附（RSA）模型对QCM-D数据进行进一步分析，确定了吸附速率参数ka和覆盖面积（a），这支持了在Δf和ΔD/Δf值中观察到的趋势。通过对QCM-D共振频率数据进行RSA建模得到的ka值，与QCM-D测量的质量与文献中光学技术报道的质量之比相匹配。我们得出结论，将通过对QCM-D数据进行RSA建模获得的吸附速率参数（ka）与通过对使用光学技术获得的数据进行RSA建模获得的ka值进行比较，可能是确定吸附蛋白层水合程度的一种途径。
