Lieberzeit, P., Afzal, A., Rehman, A., & Dickert, F. (2007). Nanoparticles for detecting pollutants and degradation processes with mass-sensitive sensors. Sensors and Actuators B: Chemical, 127(1), 132–136.
Abstract: Compared with thin films, nanoparticle layers as coatings for QCM offer substantially increased interaction areas and sensitivities with favourable response times. Molybdenum disulphide (MoS2), e.g. has turned out to be a highly suitable material for interacting with thiols. The resulting materials are sufficiently soft according to Pearson to bind sulphur containing compounds reversibly. Depositing MoS2 nanoparticle submonolayers (particle size 200–300 nm) leads to an increase in sensor response by a factor of ten compared to a pure gold layer. Additionally, the nanoparticle layers show fully reversible sensor signals. Particle synthesis can also be combined with the molecular imprinting approach: by a precipitation technique, it is possible to generate molecularly imprinted TiO2 particles for engine oil degradation measurements. Compared with deposited thin layers, particles incorporate oxidised compounds from lubricants by a factor of two better.
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Dickert, F. L., Haunschild, A., Kuschow, V., Reif, M., & Stathopulos, H. (1996). Mass-sensitive detection of solvent vapors. Mechanistic studies on host-guest sensor principles by FT-IR spectroscopy and BET adsorption analysis. Anal. Chem., 68(6), 1058–1061.
Abstract: Chemical sensors, based on highly mass sensitive QMB or SAW devices, coated with thin layers of calixarenes, enable the detection of organic solvent vapours, especially halogenated or aromatic hydrocarbons, down to a few ppm. Force field calculations allow the tailoring of these sensor materials seeing that the predicted interaction energies between the host molecules and a large variety of analytes are linearly correlated to the measured sensor effects. These correlations and also BET adsorption analysis prove the analyte recognition properties of these calixarene coatings to be mainly based on host/guest inclusion principles.
Keywords: supramolecular recognition, quartz crystal microbalance, QCM, surface acoustic wave, SAW, mass-sensitive sensor, detector, calixarenes, MM3 force field, Brunauer, Emmett and Teller theory, BET
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