The gravimetric analysis of electrodeposited nickel is demonstrated using electrochemical quartz crystal microbalance (EQCM) where the nickel coatings come from a solution of the metal chloride salt separately in eith...The gravimetric analysis of electrodeposited nickel is demonstrated using electrochemical quartz crystal microbalance (EQCM) where the nickel coatings come from a solution of the metal chloride salt separately in either a1choline chloride: 2 ethylene glycol (ethaline) or 1 choline chloride: 2 urea (reline) based ionic liquid. The possibility of adapting the Quartz Crystal Microbalance EQCM (which measures the mass attached to the electrode) to probe kinetics of electrochemically-driven solid state phase transformations has been explored in a Ni electrodeposition in absence and presence of complexing agents ethylene diamine en and acetylacetonate acac from both electrolytes ethaline and reline. The study shows that the current efficiency and the rate of deposition of nickel coatings obtained from ethaline and reline baths in absence of brighteners en and acac are different, and the addition of en and acac to both ionic liquid solutions results in a significant decrease current. And the associated growth rate will also be decreased, suggesting that the en acac stops the formation and growth of Ni nuclei. This suggests that the mechanism of growth is changed.展开更多
We have investigated the interactions between phospholipid monolayers and volatile anest-hatics. Two monolayers (dihexadecyl phosphate (DHP) and dipalmitoyl phosphatidyl choline (DPPC) and two anesthetics (halothane a...We have investigated the interactions between phospholipid monolayers and volatile anest-hatics. Two monolayers (dihexadecyl phosphate (DHP) and dipalmitoyl phosphatidyl choline (DPPC) and two anesthetics (halothane and enflurane) were used to observe these interac-tions using a highly sensitive quartz crystal microbalance (HS-QCM). The concentration of each anesthetic in aqueous solution was kept at 4 mM. The frequency of QCM showed no change when halothane was added to the DHP monolayer, however, it responded and de-creased when interaction occurred with DPPC monolayer. In case of enflurane addition the frequency decreased in both the monolayers of DHP and DPPC. The frequency change followed the following order of monolayer-anesthetic interactions: DHP-halothane <DPPC-halothane <DHP-enflurane <DPPC-enflurane. These re-sults showed that the response of anesthetics to the monolayers i.e. the physisorption not only depends on the anesthetic structure, the type of anesthetic hydrate formed, but also the hydrophilic polar group structure of the monolayer or the monolayer/water interface had an important role in physisorption.展开更多
An electronic-nose is developed based on eight quartz-crystal-microbalance (QCM) gas sensors in a sensor box, and is used to detect Chinese liquors at room temperature. Each sensor is a highly-accurate and highly-sens...An electronic-nose is developed based on eight quartz-crystal-microbalance (QCM) gas sensors in a sensor box, and is used to detect Chinese liquors at room temperature. Each sensor is a highly-accurate and highly-sensitive oscillator that has experienced airflow disturbances under the condition of varying room temperatures due to unstable flow-induced forces on the sensors surfaces. The three-dimensional (3D) nature of the airflow inside the sensor box and the interactions of the airflow on the sensors surfaces at different temperatures are studied by computational fluid dynamics (CFD) tools. Higher simulation accuracy is achieved by optimizing meshes, meshing the computational domain using a fine unstructural tetrahedron mesh. An optimum temperature, 30 ℃, is obtained by analyzing the distributions of velocity streamlines and the static pressure, as well as the flow-induced forces over time, all of which may be used to improve the identification accuracy of the electronic-nose for achieving stable and repeatable signals by removing the influence of temperature.展开更多
Nanoparticles are playing an increasingly important role in the development of biosensors. The sensitivity and performance of biosensors are being improved by using Nanoparticles for their construction. The use of the...Nanoparticles are playing an increasingly important role in the development of biosensors. The sensitivity and performance of biosensors are being improved by using Nanoparticles for their construction. The use of these Nanoparticles has allowed the introduction of many new signal transduction technologies in biosensors. In this report, a comprehensive review of application of nanoparticles in Quartz Crystal Microbalance biosensors is presented. The main advantages of QCM in sensing fields include high sensitivity, high stability, fast response and low cost. In addition, it provides label-free detection capability for bio-sensing applications. Firstly, basic QCM’s design and characterization are described. Next, QCM biosensors based on modification of quartz substrate structure and their applications are digested. Nanoparticles and their utilizationin analysis are then illustrated. These include Nanoparticles in bio applications that cover Nanoparticles in Quartz Crystal Microbalance biosensors.展开更多
We are developing methods to quantify antibody interactions that include a quartz crystal microbalance (QCM) system to measure, on a molecular basis, the interaction of p53 and anti-p53 antibodies. Previously, as a mo...We are developing methods to quantify antibody interactions that include a quartz crystal microbalance (QCM) system to measure, on a molecular basis, the interaction of p53 and anti-p53 antibodies. Previously, as a model system, we developed a measurement device consisting of p53 protein (human wild type), characterized by mass spectroscopy and immobilized at various concentrations on a glass slide. The device is designed as a control to be used with immunohistochemical (IHC) assays that incorporate commercially available anti-p53 antibodies and probes. In the current study, p53 protein is covalently immobilized on a silicon dioxide-coated quartz crystal and the resonance frequency shift is followed in-situ. The functionalized sensor is then incubated with the anti-p53 antibody, which provides a direct gravimetric measure of the antibody-antigen binding. This previously described method allows the comparison of the surface immobilized protein concentrations with estimates obtained by fluorescence measurement. The p53 functionalized QCM system offers an independent measure of surface immobilized protein concentration and is essential in development of our IHC calibration prototypes. These results provide a benchmark for comparing antibody systems that may be used in developing other molecular diagnostic assays such as immunocytochemical analysis and the detection of biomarker proteins in blood and urine.展开更多
The "solidified liquid layer" model has been examined using a quartz crystal microbalance(QCM) with a polymeric matrix.The model is shown to give a reasonable explanation for the following experimental obser...The "solidified liquid layer" model has been examined using a quartz crystal microbalance(QCM) with a polymeric matrix.The model is shown to give a reasonable explanation for the following experimental observations:(i) The opposite response of the QCM and surface plasmon resonance(SPR) for the activation process;(ii) the marked difference in the responses for IgG/anti-IgG interaction between QCM and SPR.Theoretical analysis and experimental results indicated that QCM is sensitive to the thickness change of the "solidified liquid layer" but not the mass of captured biomolecules(i.e.,the immobilized mass),implying caution must be taken in interpreting QCM results.展开更多
文摘The gravimetric analysis of electrodeposited nickel is demonstrated using electrochemical quartz crystal microbalance (EQCM) where the nickel coatings come from a solution of the metal chloride salt separately in either a1choline chloride: 2 ethylene glycol (ethaline) or 1 choline chloride: 2 urea (reline) based ionic liquid. The possibility of adapting the Quartz Crystal Microbalance EQCM (which measures the mass attached to the electrode) to probe kinetics of electrochemically-driven solid state phase transformations has been explored in a Ni electrodeposition in absence and presence of complexing agents ethylene diamine en and acetylacetonate acac from both electrolytes ethaline and reline. The study shows that the current efficiency and the rate of deposition of nickel coatings obtained from ethaline and reline baths in absence of brighteners en and acac are different, and the addition of en and acac to both ionic liquid solutions results in a significant decrease current. And the associated growth rate will also be decreased, suggesting that the en acac stops the formation and growth of Ni nuclei. This suggests that the mechanism of growth is changed.
文摘We have investigated the interactions between phospholipid monolayers and volatile anest-hatics. Two monolayers (dihexadecyl phosphate (DHP) and dipalmitoyl phosphatidyl choline (DPPC) and two anesthetics (halothane and enflurane) were used to observe these interac-tions using a highly sensitive quartz crystal microbalance (HS-QCM). The concentration of each anesthetic in aqueous solution was kept at 4 mM. The frequency of QCM showed no change when halothane was added to the DHP monolayer, however, it responded and de-creased when interaction occurred with DPPC monolayer. In case of enflurane addition the frequency decreased in both the monolayers of DHP and DPPC. The frequency change followed the following order of monolayer-anesthetic interactions: DHP-halothane <DPPC-halothane <DHP-enflurane <DPPC-enflurane. These re-sults showed that the response of anesthetics to the monolayers i.e. the physisorption not only depends on the anesthetic structure, the type of anesthetic hydrate formed, but also the hydrophilic polar group structure of the monolayer or the monolayer/water interface had an important role in physisorption.
基金Project supported by the National Natural Science Foundation of China(Nos.61876059 and U1501251)
文摘An electronic-nose is developed based on eight quartz-crystal-microbalance (QCM) gas sensors in a sensor box, and is used to detect Chinese liquors at room temperature. Each sensor is a highly-accurate and highly-sensitive oscillator that has experienced airflow disturbances under the condition of varying room temperatures due to unstable flow-induced forces on the sensors surfaces. The three-dimensional (3D) nature of the airflow inside the sensor box and the interactions of the airflow on the sensors surfaces at different temperatures are studied by computational fluid dynamics (CFD) tools. Higher simulation accuracy is achieved by optimizing meshes, meshing the computational domain using a fine unstructural tetrahedron mesh. An optimum temperature, 30 ℃, is obtained by analyzing the distributions of velocity streamlines and the static pressure, as well as the flow-induced forces over time, all of which may be used to improve the identification accuracy of the electronic-nose for achieving stable and repeatable signals by removing the influence of temperature.
文摘Nanoparticles are playing an increasingly important role in the development of biosensors. The sensitivity and performance of biosensors are being improved by using Nanoparticles for their construction. The use of these Nanoparticles has allowed the introduction of many new signal transduction technologies in biosensors. In this report, a comprehensive review of application of nanoparticles in Quartz Crystal Microbalance biosensors is presented. The main advantages of QCM in sensing fields include high sensitivity, high stability, fast response and low cost. In addition, it provides label-free detection capability for bio-sensing applications. Firstly, basic QCM’s design and characterization are described. Next, QCM biosensors based on modification of quartz substrate structure and their applications are digested. Nanoparticles and their utilizationin analysis are then illustrated. These include Nanoparticles in bio applications that cover Nanoparticles in Quartz Crystal Microbalance biosensors.
文摘We are developing methods to quantify antibody interactions that include a quartz crystal microbalance (QCM) system to measure, on a molecular basis, the interaction of p53 and anti-p53 antibodies. Previously, as a model system, we developed a measurement device consisting of p53 protein (human wild type), characterized by mass spectroscopy and immobilized at various concentrations on a glass slide. The device is designed as a control to be used with immunohistochemical (IHC) assays that incorporate commercially available anti-p53 antibodies and probes. In the current study, p53 protein is covalently immobilized on a silicon dioxide-coated quartz crystal and the resonance frequency shift is followed in-situ. The functionalized sensor is then incubated with the anti-p53 antibody, which provides a direct gravimetric measure of the antibody-antigen binding. This previously described method allows the comparison of the surface immobilized protein concentrations with estimates obtained by fluorescence measurement. The p53 functionalized QCM system offers an independent measure of surface immobilized protein concentration and is essential in development of our IHC calibration prototypes. These results provide a benchmark for comparing antibody systems that may be used in developing other molecular diagnostic assays such as immunocytochemical analysis and the detection of biomarker proteins in blood and urine.
基金supported by the 100 Talents Programme of Chinese Academy of Sciences(08BM031001)the Fok Ying Tung Education Foundation (114013) to H.M.the National Basic Research Program of China (2009CB320300)
文摘The "solidified liquid layer" model has been examined using a quartz crystal microbalance(QCM) with a polymeric matrix.The model is shown to give a reasonable explanation for the following experimental observations:(i) The opposite response of the QCM and surface plasmon resonance(SPR) for the activation process;(ii) the marked difference in the responses for IgG/anti-IgG interaction between QCM and SPR.Theoretical analysis and experimental results indicated that QCM is sensitive to the thickness change of the "solidified liquid layer" but not the mass of captured biomolecules(i.e.,the immobilized mass),implying caution must be taken in interpreting QCM results.
