A novel ion-selective sensor for procaine hydrochloride has been proposed and applied successfully to analysis of pharmaceutical
preparations. The sensor is based on modification of the Ag-electrode of an AT-cut piezoelectric quartz crystal with a PVC
membrane containing procaine tetraphenylborate. A linear relation between the logarithm of the response frequency and the
logarithm of the procaine hydrochloride concentration was found experimentally and could be explained by combination of a
modified Sauerbrey equation and the Freundlich isotherm. The detection range was from 8.3 × 10−8 to 5.0 × 10−3 M with a detection limit of 8.3 × 10−8 M. The selectivity of the sensor and the influence of experimental parameters such as solution pH and detection time were
investigated.
Received February 10, 1999. Revision October 10, 1999. 相似文献
Abstract Sulfur dioxide was detected and determined in air by a piezoelectric quartz crystal sensor coated with 4-aminoantipyrine 1-hydroxyetil-2-heptadecenyl imidazol (amine 220) solution (1:1 v/v in chloroform). The analytical response curve is linear over the concentration range from 0.70 to 5.0 ppm of SO2. Good linearities (r = 0.9990, 0.9995 and 0.9968) and sensitivities (18.0, 33.4 and 50.7 Hz/ppm) were found, respectively for exposure times of 30, 60 and 90 seconds. The sensor can be used for more than six months without loss in sensitivity and presented good reversibility and reproducibility. Among some possible interferents tested, only nitrogen dioxide and moisture caused major frequency changes. 相似文献
ABSTRACT A new method for mutagenicity testing of carcinogens is proposed in this paper. Mutagenic activity is examined through monitoring of the growth situation of Salmonella typhimurium TA98 strain with a series piezoelectric quartz crystal (SPQC) sensor. This method needs no immobilization and preincubation of microorganism, and is simple and rapid. It can be applied to detect mutagen directly. When it was used to study the mutagenicity of dimethyl sulfate, the test time was 4 h at 37°C. There was a good linear relationship between frequency shift and the dose of mutagen in the range 2.5-20 μg/mL and the regression equation was ∠F = 53.82 + 3.81C. Some experimental conditions are also discussed in detail. 相似文献
Abstract A novel piezoelectric quartz crystal microbalance (QCM) device with gas permeable membrane is proposed for the detection of microorganisms producing hydrogen sulfide (H2S). The detection theory is based on the adsorption of hydrogen sulfide onto the silver electrode of the piezoelectric crystal sensor, which causes a dramatic decrease in the resonant frequency of QCM. A 100 Hz frequency shift is chosen as the criteria value to judge the presence of microorganisms producing H2S. Factors affecting detection were investigated. Desiccant is of great practical importance in sensor response. This new biosensor can be a potential candidate for detecting bacteria which produce hydrogen sulfide. 相似文献
Thin, phenylboronic acid‐containing polymer coatings are potentially attractive sensory layers for a range of glucose monitoring systems. This contribution presents the synthesis and properties of glucose‐sensitive polymer brushes obtained via surface RAFT polymerization of 3‐methacrylamido phenylboronic acid (MAPBA). This synthetic strategy is attractive since it allows the controlled growth of PMAPBA brushes with film thicknesses of up to 20 nm via direct polymerization of MAPBA without the need for additional post‐polymerization modification or deprotection steps. QCM‐D sensor chips modified with a PMAPBA layer respond with a linear change in the shift of the fundamental resonance frequency over a range of physiologically relevant glucose concentrations and are insensitive toward the presence of fructose, thus validating the potential of these polymer brush films as glucose sensory thin coatings.
An unexpected frequency response for a piezoelectric quartz crystal (PQC) sensor to liquid density and viscosity was reported. For a PQC oscillating in a liquid phase, the frequency shifts (△f) show a wave-shape response to liquid density (p) and viscosity 03) in fine structure, ifthe longitudinal wave effect was not eliminated. This result is different from the well-knownlinear relationship between of Af and (ρη)1/2. An oscillating frequency-temperature curve of thesensor was observed and explained. 相似文献
