Piezoelectric sorption

Differential Vapor Pressure. Gravimetric Sorption, and Piezoelectric Sorption Methods... 

King, W.H. Piezoelectric sorption detector. Anal. Chem. 1964, 36, 1735. 

Mueller P, Rudin D O, Tien H T and Wescott W 1962 Reconstruction of excitable cell membrane structure in vitro Circulation 26 1167-71 King W H Jr 1964 Piezoelectric sorption detector Ana/, Chem. 36 1735-9 Guilbault G and Montalvo J 1969 A urea specific enzyme electrode J. Am. Chem. Soc. 91 2164-5... 

King (5) reported that the first crystal sorption detector was the "Martini Detector", a fun project he started in the basement of his house. He coated the crystals in his ham radio transmitter with the insect repellent (di-n-butylphthalate), and found that the frequency shifted more when the coating was exposed to alcoholic breath than to normal breath. Out of that fun project came the pioneering work of King in the development of the piezoelectric sorption detector. The high sensitivity, simplicity, and ruggedness of the piezoelectric sorption detector led to a variety of applications in air pollution research. 

Isopiestic sorption/desorption methods, i.e., gravimetric sorption, piezoelectric sorption, or isothermal distillation... 

WH. King, Piezoelectric sorption sensor. Anal. Chem. 36(9), 1735-1739 (1964)... 

The piezoelectric sorption technique is a method that is especially suitable for the low solvent concentration range. It is the most sensitive solvent vapor sorption method. A resolution of nanograms can be realized. Measurements can also be made as a function of time... 

In summary, die decision for a special equipment depends to some extend on concentration, temperature and pressure ranges one is interested in. From the experience of the author, the combination of isopiestic vapor pressure/vapor sorption measurements for the determination of solvent activities with infinite dilution IGC for the determination of Henry s constants provides good experimental data and covers a temperature range that is broad enough to have a sufficient data basis for thermodynamic modeling. If one is interested in both solvent solubiUty and diffusion data, finite concentration IGC or piezoelectric sorption techniques should be applied. 

Justino CIL, Rocha-Santos TA, Duarte AC, Rocha-Santos TA (2010) Review of analytical figures of merit of sensors and biosensors in clinical applications. Trends Anal Chem 29(10) 172-1183 Keefe MK, Benkstein KD, Hup JT (2000) Luminescent sensor molecules based on coordinated metals a review of recent developments. Coord Chem Rev 205(l) 201-228 Kharitonov SA, Barnes PJ (2000) CUnical aspects of exhaled nitric oxide. Eur Respir J 16 781-792 King WH Jr (1964) Piezoelectric sorption detector. Anal Chem 36 1735-1739... 

The most sensitive solvent vapor sorption method is the piezoelectric sorption detector. The amount of solvent vapor absorbed by a polymer is detected by a corresponding change in frequency of a piezoelectric quartz crystal coated with a thin film of the polymer because a frequency change is the response of a mass ehange at the surface of such a crystal. The frequency of the crystal decreases as mass increases when the crystal is placed in a gas or vapor medium. The frequency decrease is fairly hnear. The polymer must be coated onto the crystal from a solution with some care to obtain a fairly uniform film. Measurements can be made at dynamic (vapor flow) or static conditions. With reasonable assumptions for the stabihty of the crystal s base frequency and the precision of the frequency counter employed, the piezoelectric method allows the detection of as little as 10... 

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