Chemical And Biological Molecole Recognition Based On QCM Sensing Device

Because of the superiority of high sensitivity and selectivity, piezoelectric quartz crystal microbalance (QCM) have been widely used in the preparation of various types of chemical and biological sensors. In this thesis, QCM gas and liquid device designed on the basis of existing instruments in the laboratory, were conducted a series of gas phase and liquid phase detection experiment.Four calixarene derivatives were employed as adsorptive coating materials of quartz crystal microbalance (QCM) for detection of ethanol gas in environmental atmosphere, indicating that C-ethylcalix[4]pirogallarene (Ⅲ) was the most effectively active material to ethanol. By the preparation of the single crystal of Ⅲ·2CH3CH2OH and analysis of the structure of X-ray diffraction, finding out that the recognition mechanism between the supramolecular host calixarene Ⅲ and the guest ethanol molecule was based on the formation of C-H...π, O-H...π and O-H...O hydrogen bonds interaction. With good selectivity, reversibility, reproducibility, stability, rapid test time and a recovery of94.8～105.2%, the QCM sensor coating with III could be applied to detecting ethanol samples, which was in well consistent with gas chromatography, indicating the potential application prospect in detecting trace amounts of ethanol gas in living environment.In this paper, self-assembled monolayers were constructed on the surface of gold electrode, which developing into a new piezoelectric immunosensor. First, the electrode surface was modified with L-cysteine. Then the antibody of the c-myc was covalent crosslinked onto the QCM surface by glutaraldehyde for the detection of antigene via immunoreaction. The antibody immobilization conditions have been investigated in details. The glutaraldehyde binding procedure provides higher antibody activity and larger frequency response on the immunoreaction. The biosensor was simply prepared which possessed nice selectivity, reproducibility, stability and regenerability, and could be applied for determination of c-myc in rat serum with a recovery of90.7%～115.6%, indicating its practical application on detection of c-myc in tumor samples with potential value in biomedical field. In addition, because of the immobilized methods was widely used in protein molecules, low effected on the activity of antibody molecules, is expected to be used for detecting other biological macromolecules.