125I-Radiolabeling, Surface Plasmon Resonance, and Quartz Crystal Microbalance with Dissipation: Three Tools to Compare Protein Adsorption on Surfaces of Different Wettability
Yafei Luan †, Dan Li *†(李丹), Yanwei Wang †, Xiaoli Liu †, John L. Brash †‡, and Hong Chen *†（陈红）
† Jiangsu Key Laboratory of Advanced Functional Polymer Design and Application, Department of Polymer Science and Engineering, College of Chemistry, Chemical Engineering and Materials Science, Soochow University, 199 Ren-ai Road, Suzhou 215123, PR China
‡ School of Biomedical Engineering and Department of Chemical Engineering, McMaster University, Hamilton, Ontario, Canada
Langmuir 2014, 30, 1029–1035.
The extent of protein adsorption is an important consideration in the biocompatibility of biomaterials. Various experimental methods can be used to determine the quantity of protein adsorbed, but the results usually differ. In the present work, self-assembled monolayers (SAMs) were used to prepare a series of model gold surfaces varying systematically in water wettability, from hydrophilic to hydrophobic. Three commonly used methods, namely, surface plasmon resonance (SPR), quartz crystal microbalance with dissipation (QCM-D), and 125I-radiolabeling, were employed to quantify fibrinogen (Fg) adsorption on these surfaces. This approach allows a direct comparison of the mass of Fg adsorbed using these three techniques. The results from all three methods showed that protein adsorption increases with increasing surface hydrophobicity. The increase in the mass of Fg adsorbed with increasing surface hydrophobicity in the SPR data was parallel to that from 125I-radiolabeling, but the absolute values were different and there does not seem to be a “universally congruent” relationship between the two methods for surfaces with varying wettability. For QCM-D, the variation in protein adsorption with wettability was different from that for SPR and radiolabeling. On the more hydrophobic surfaces, QCM-D gave an adsorbed mass much higher than from the two other methods, possibly because QCM-D measures both the adsorbed Fg and its associated water. However, on the more hydrophilic surfaces, the adsorbed mass from QCM-D was slightly greater than that from SPR, and both were smaller than from 125I-radiolabeling; this was true no matter whether the Sauerbrey equation or the Voigt model was used to convert QCM-D data to adsorbed mass.
链接： //pubs.acs.org/doi/abs/10.1021/la403498w
