AVS 50th International Symposium
    Biomaterial Interfaces Tuesday Sessions
       Session BI-TuP

Paper BI-TuP8
Operation of the QCM-D Technique at Elevated Oscillation Amplitudes

Tuesday, November 4, 2003, 5:30 pm, Room Hall A-C

Session: Poster Session
Presenter: M.E.M. Edvardsson, Chalmers University of Technology, Sweden
Authors: M.E.M. Edvardsson, Chalmers University of Technology, Sweden
F. Höök, Chalmers University of Technology, Sweden
Correspondent: Click to Email
An often raised question with respect to applications of the quartz crystal microbalance technique is whether the shear oscillation of the sensor surface influences the measured binding events. This is indeed a relevant question, especially since solid proofs for bond rupture at elevated amplitudes was recently presented.@footnote 1,2@ In part inspired by these observations, our QCM-D device has been further developed to operate at variable driving amplitudes (from 1 V to 10 V corresponding to maximum oscillation amplitude between 4nm and 40nm), while still maintaining the possibility to perform combined f and D measurements - a combination that was not implemented in previous work. In order to test the device, we choose the well established process by which intact vesicles adsorb and decompose into a planar supported lipid bilayer on SiO@sub 2@, known to be very sensitive to external perturbations. Up to driving amplitudes of 2V, the adsorption behavior is essentially unaffected, whereas it becomes significantly affected at driving amplitudes above 2V. These results thus nicely demonstrate the possibility to implement variable driving amplitudes, and proves that an entirely new dimension will be possible to explore in detail, especially when combined with f and D data at multiple harmonics and proper theoretical modeling is implemented: The amplitude variation can be used to either affect the system being studied, or to extract new information about it by going from the harmonic to the anharmonic regime, which will be discussed in this paper. @FootnoteText@ @footnote 1@Cooper MA, et al.; Direct and sensitive detection of a human virus by rupture event scanning. Nature Biotechnology 2001, 19:833-837@footnote 2@Dultsev FN, et al.; "Hearing" bond breakage. Measurement of bond rupture forces using a quartz crystal microbalance. Langmuir 2000, 16:5036-5040.