Title of article :
Variations in Coupled Water, Viscoelastic Properties, and Film Thickness of a Mefp-1 Protein Film during Adsorption and Cross-Linking: A Quartz Crystal Microbalance with Dissipation Monitoring, Ellipsometry, and Surface Plasmon Resonance Study
Author/Authors :
Sott، Kristin نويسنده , , H??k، Fredrik نويسنده , , Kasemo، Bengt نويسنده , , Nylander، Tommy نويسنده , , Fant، Camilla نويسنده , , Elwing، Hans نويسنده ,
Issue Information :
دوهفته نامه با شماره پیاپی سال 2001
Pages :
-5795
From page :
5796
To page :
0
Abstract :
We have measured the time-resolved adsorption kinetics of the mussel adhesive protein (Mefp-1) on a nonpolar, methyl-terminated (thiolated) gold surface, using three independent techniques: quartz crystal microbalance with dissipation monitoring (QCM-D), surface plasmon resonance, and ellipsometry. The QCM-D and ellipsometry data shows that, after adsorption to saturation of Mefp-1, cross-linking of the protein layer using NaIO4 transforms it from an extended (~20 nm), water-rich, and hydrogel-like state to a much thinner (~5 nm), compact, and less water-rich state. Furthermore, we show how quantitative data about the thickness, shear elastic modulus, and shear viscosity of the protein film can be obtained with the QCM-D technique, even beyond the Sauerbrey regime, if frequency (f) and energy dissipation (D) measurements measured at multiple harmonics are combined with theoretical simulations using a Voight-based viscoelastic model. The modeling result was confirmed by substituting H2O for D2O. As expected, the D2O substitution does not influence the actual adsorption behavior, but resulted in expected differences in the estimated effective density and shear viscosity. These results provide new insight and understanding about the adsorption kinetics and cross-linking behavior of Mefp-1. They also demonstrate how the above three techniques complement each other for biomolecule adsorption studies.
Keywords :
red clover , Trifolium pratense , Isoflavone glycoside 6"-O-acetates , Isoflavone glycoside 6"-O-malonates , Solid-phase extraction (SPE) , High-performance liquid chromatography-mass spectrometry (LC-MS)
Journal title :
Analytical Chemistry
Serial Year :
2001
Journal title :
Analytical Chemistry
Record number :
51950
Link To Document :
بازگشت