Showing papers by "Shouzhuo Yao published in 1999"
TL;DR: A bio-mimic bulk acoustic wave sensor fabricated by coating the caffeine (CAF) template molecular imprinting polymer (MIP) with high selectivity and a sensitive mass response to CAF proved to be a convenient method with the advantages of high sensitivity, good selectivity, ease of handling.
Abstract: A bio-mimic bulk acoustic wave (BAW) sensor was fabricated by coating the caffeine (CAF) template molecular imprinting polymer (MIP). This sensor exhibited high selectivity and a sensitive mass response to CAF. The response range of the sensor was between 5.0 × 10–9 and 1.0 × 10–4 M with a detection limit of 5.0 × 10–9 M at pH 8.0. Recoveries were 96.1–105.6%. Influencing factors were investigated in detail and optimized. When employed to detect real samples, the proposed method proved to be a convenient method with the advantages of high sensitivity, good selectivity and ease of handling.
70 citations
TL;DR: In this paper, a new method for biochemical oxygen demand (BOD) determination, which combines the series piezoelectric quartz crystal (SPQC) technique with the growth of a microorganism is presented.
17 citations
TL;DR: In this article, the growth process of Cu-MBT complex film was monitored by the bulk acoustic wave (BAW) sensor under open-circuit condition and the frequency shift curves were acquired.
15 citations
TL;DR: In this article, a thickness-shear mode piezoelectric quartz crystal (PQC) was used to fabricate a trimethoprim (TMP) ion-selective sensor for the determination of TMP.
Abstract: PVC film containing various activants was coated on one electrode of a thickness-shear mode piezoelectric quartz crystal (PQC) to fabricate a trimethoprim (TMP) ion-selective piezoelectric sensor for the determination of TMP The method is based on the selective adsorption of TMP ion on the modified film and the sensitive mass response of the PQC The method was found to be sensitive, rapid and easy to handle with no need for previous sample treatment The logarithm of frequency shift of PQC was found to bear a linear relationship to the logarithm of the concentration of TMP over the range 2 × 10–8–2 × 10–3M with a detection limit of 2 × 10–8M at pH 40 Recoveries were from 99–1029% Two activants, TMP phosphotungstate and TMP silicotungstate, were synthesized and investigated Influencing factors were examined in detail and optimized The results for real samples obtained by the proposed method agreed with those obtained by a conventional method
14 citations
TL;DR: A non-suppressed ion-chromatographic assay combined with a novel double cell quartz crystal (DCQC) detector is developed for analysis of different valency chlorine species including chlorite, chloride, chlorate, hypochlorite.
12 citations
TL;DR: In this paper, a robust complex non-linear regression, called complex least trimmed squares regression (CLTSR), is described and utilized in the parameter estimation to alleviate the fluctuation in thickness-shear-mode (TSM) acoustic wave sensor.
8 citations
TL;DR: In this article, a method for determination of lysozyme with a Bulk Acoustic Wave (BAW) viscosity sensor is presented, based on the bacteriolytic action of Lysozyme on Micrococcus lysodeikeicus and the response of the sensor to the visosity and density change of this process.
Abstract: A method for determination of lysozyme with a Bulk Acoustic Wave (BAW) viscosity sensor is presented. It is based on the bacteriolytic action of lysozyme on Micrococcus lysodeikeicus (M. lysodeikeicus) and the response of the sensor to the viscosity and density change of this process. There was a good correlation between the frequency shift and the concentration of lysozyme in the range 10–100 μg/ml. The content of lysozyme in human saliva was determined by this method and the results obtained were in good agreement with those from the conventional turbidimetric method. This method has an advantage over the conventional turbidimetric method in that the amount of sample needed is smaller, the procedure is simpler and the concentration range of the bacterium suspension which can be used in the detection was extended.
7 citations
TL;DR: The method exhibits a sensitive, rapid response and is easy to operate without pretreatment of the sample, and the results for real samples obtained by the proposed method agreed with those obtained by conventional methods.
Abstract: The method describes the use of a piezoelectric quartz crystal (PQC) as a substitute for ion-selective electrodes. The approach is feasible when the membrane materials are electrically non-conductive and membrane potential measurements are consequently not possible. An ion-selective piezoelectric sensor sensitive to atropine sulfate was constructed by coating a PVC membrane containing activant on one side of a PQC. On the basis of selective adsorption of atropine ions across the modified film and the sensitive mass response of PQC, the method exhibits a sensitive, rapid response and is easy to operate without pretreatment of the sample. The logarithm of the frequency shift gave a linear relationship with the logarithm of atropine sulfate concentration in the 1.0 × 10–8–1.0 × 10–3 M range with a detection limit of 5.0 × 10–9 M at pH 7.0. Recoveries were from 98.7–102.2%. Two activants, atropine tetraphenylborate and atropine dipicrylaminate, were synthesized and investigated. Influencing factors were also examined and optimized. The results for real samples obtained by the proposed method agreed with those obtained by conventional methods.
5 citations
TL;DR: In this article, an ion-selective piezoelectric (ISP) sensor was fabricated by coating an active film which has selective adsorption/desorption properties for the chlorpheniramine (CPM) cation onto one electrode of an AT-cut piezolectric quartz crystal which is known for its sensitive mass response.
3 citations
TL;DR: In this article, an electrodeless piezoelectric quartz crystal was used to measure mass changes on the surface of a quartz plate during the reduction of Ag(NH 3 ) + 2 by glucose.
3 citations
TL;DR: A reliable ion-chromatographic method with a novel double chamber bulk acoustic wave (DCBAW) detector was developed for monitoring five important inorganic cations in biological culture media and showed that the consumption velocities of Mg(2+) and K(+) are related to the growth of the cells and decrease fastest during the first 2-5 h.
TL;DR: In this article, a series piezoelectric quartz crystal (SPQC) was applied to continuously determine the variation of frequency shift during the culture of Thiobacillus ferrooxidans, with a conductive electrode as the probe.
Abstract: A rapid and simple method for monitoring the growth of Thiobacillus ferrooxidans is put forward by using a series piezoelectric quartz crystal (SPQC). The SPQC was applied to continuously determine the variation of frequency shift during the culture of Thiobacillus ferrooxidans, with a conductive electrode as the probe. The frequency shift as a function of time agrees with a typical 'S - shape' model, a piezoelectric sensor responding well to the growth of Thiobacillus ferrooxidans. The fundamentals for determination of the bacterial growth activity using the SPQC is also described; the frequency shift is only dependent on the electrical conductivity of the solution and the dielectric constant.
TL;DR: Ion chromatography (IC) with series bulk acoustic wave (SBAW) detection was developed for monitoring of phosphate, chloride and sulfate during the cultivation of Cephalosporium acremonium and production of cepsporin C.
TL;DR: A protein denaturation piezoelectric frequency shift method was used to determine the number of bacteria based on the influence of bacterium metabolism on milk, which was more rapid, as less than half an hour was needed for detection after a preincubation of several hours.