Quartz Crystal Microbalance as a Sensor to Characterize Macromolecular Assembly Dynamics
Figure 17
QCM-D signiatures for structural transformation from intact vesicles to a supported bilayer induced by AH peptide. (a) QCM-D adsorption kinetics of the first four overtones ( where vesicles in a Tris buffer solution (150 mM NaCl, pH 7.5) onto a gold surface. Vesicles are added after stabilizing the frequency signal for 10 minutes (see arrow 1). The film was then washed twice with the same buffer (see arrows 2 and 3). Upon addition of the AH peptide (see arrow 4), the vesicles rupture and form a bilayer on the gold surface. Two buffer washes were performed in order to ensure the stability of the film (see arrows 5 and 6). (b) Expanded view of (a). It is a detailed plot of AH peptide-induced vesicle rupture process from 50 to 75 minutes. The markers are also presented in order to distinguish the traces of the overtones (open star , open circle , open triangle , and open square , respectively. (c) Usie of a Voigt-based model to fit as shown in Figure 17(a) for the structural transformation from intact vesicles to a supported bilayer. The fit between the viscoelastic model (-Tools with density kg/m3) and the experimental data are presented. (d) Corresponding energy dissipation versus time plot demonstrates that the viscoelastic nature of the film changes during the structural transformation from soft vesicle layer to a rigid bilayer. (e) Expanded view of (c) to capture energy dissipation change corresponding to vesicle-AH peptide interaction. (f) Corresponding fit using same model. Reprint from [37].
