Coated surface acoustic wave

Grate, J.W., Abraham, M.H., Du, C.M., et al. (1995). Examination of vapor sorption by fiillerene, fullerene-coated surface acoustic wave sensonrs, graphite, and low-polarity polymers using hnear solvation energy relationships. Langmuir, 11, 2125-30. 

FIGURE 4.7 SAW velocity and attenuation changes vs. shear wave phase shift (i) for several values of film loss parameter. The dashed line corresponds to prediction using Tiersten formula. (Reprinted with permission from Martin S. J., Frye G. C., and Senturia S. D., Dynamics and response of polymer-coated surface acoustic wave devices Effect of viscoelastic properties and film resonance, Anal. Chem., 66, 2201-2219, 1994. Copyright (1994) American Chemical Society.)... 

Martin S. J., Frye G. C., and Senturia S. D., Dynamics and response of polymer-coated surface acoustic wave devices Effect of viscoelastic properties and film resonance. Anal. Chem., 66, 2201-2219, 1994. 

Selective Measurement of Vinyl Acetate Vapor Using a Coated Surface Acoustic Wave Oscillator... 

A coated surface-acoustic-wave (SAW) sensor capable of real-time, selective measurement of vinyl acetate vapor in the presence of several olefin and non-olefin cocontaminants is described. The coating film en loyed consists of the solid platinum-ethylene Ji-complex, trans-PtCl (ethylene)(pyridine). occluded in a polyisobutylene matrix. Exposure to vinyl acetate results in displacement of ethylene from the cott lex and formation of the vinyl acetate-substituted complex. Subsequent regeneration of the original reagent is possible by treatment with ethylene gas, in situ. A lower detection limit of 5 ppm of vinyl acetate is achieved for operation at 46 C. The industrial-hygiene applications of the sensor are discussed. 

Lin H-B, Shih J-S (2003) Fullerene C -cryptand coated surface acoustic wave quartz crystal sensor for organic vapors. Sens Actuators B 92 243-254... 

By examining the dispersion properties of surface acoustic waves, the layer thickness and mechanical properties of layered solids can be obtained using the SAM. It can be used to analyze the wear damage progress [104], and detect the defects of thermally sprayed coatings [105]. 

Amidoxime-Functionalized Coatings for Surface Acoustic Wave Detection of Simulant Vapors... 

Microsensors have the potential for selective GC detectors and also as remote sensors when combined in arrays often referred to as electronic noses . Promising microsensors include surface acoustic wave (SAW) detectors normally coated with different semi-selective polymeric layers and microelectromechanical systems (MEMS) including microcantilever sensors. The hope is that, in the future, hundreds of such microcantilevers, coated with suitable coatings, may be able to achieve sufficient selectivity to provide a cost-effective platform for detecting explosives in the presence of potentially interfering compounds in real environments. This array of... 

The piezo-electric effect of deformations of quartz under alternating current (at a frequency in the order of 10 MHz) is used by coating the crystal with a selectively binding substance, e. g. an antibody. When exposed to the antigen, an antibody-antigen complex will be formed on the surface and shift the resonance frequency of the crystal proportionally to the mass increment which is, in turn, proportional to the antigen concentration. A similar approach is used with surface acoustic wave detectors [142] or with the surface plasmon resonance technology (BIAcore, Pharmacia). 

Another state-of-the-art detection system contains a surface acoustic wave (SAW) device, which is based on a piezoelectric crystal whose resonant frequency is sensitive to tiny changes in its mass—it can sense a change of 10-1° g/cm2. In one use of this device as a detector it was coated with a thin film of zeolite, a silicate mineral. Zeolite has intricate passages of a very uniform size. Thus it can act as a molecular sieve, allowing only molecules of a certain size to pass through onto the detector, where their accumulation changes the mass and therefore alters the detector frequency. This sensor has been used to detect amounts of methyl alcohol (CH3OH) as low as 10 9 g. 

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