共查询到8条相似文献,搜索用时 15 毫秒
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Mario BoehmeAuthor Vitae Friedemann VoelkleinAuthor VitaeWolfgang EnsingerAuthor Vitae 《Sensors and actuators. B, Chemical》2011,158(1):286-291
Within the last decade there has been a great increase in the need of trace and ultra-trace explosive detection. In this report, we demonstrate a new and versatile type of chemical explosive sensors based on metal oxide nanotubes easily made, even with the need of a low budget. We describe the step-by-step procedure to fabricate a sensing chip device, beginning with the synthesis of the starting materials to the point of supersensitive measurements of PETN explosive. As a result, the whole process actually is one of the most cost-effective methods to produce explosive sensing devices reported until now. The achieved chemical sensor device will be able to detect PETN explosive down to ∼112 ppt. 相似文献
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Flammable gas sensors are essential in occupational health and safety to prevent fire or explosion in gas facilities and underground mining. Our early study demonstrated that ionic liquid (IL)/quartz crystal microbalance (QCM) gas sensors and sensor arrays were excellent for the detection of various organic vapors at both room temperature and elevated temperatures. In this paper, we developed a general method that significantly enhanced the sensitivity of the IL/QCM sensors for flammable gases detection by immobilizing IL on a conductive polymer polyaniline (PAn) template. Studies were performed to optimize the PAn oxidation states, thickness, and IL concentrations. Results showed that the sensitivity increased with increasing the PAn film thickness and the amount of IL immobilized within the PAn film. The sensitivity depended also on the oxidation state and doping state of PAn. With doped and partially oxidized PAn (emeraldine salt) the IL/QCM sensor showed the best performance. The current detection limit for methane was as low as about 115 ppm at room temperature. The sensitivity also depended on the structure of the IL used. Among the four ILs tested, two of them showed excellent sensitivities after being immobilized in the PAn film. 相似文献
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Xiuming Changzhi Kemei Kun Zongbao K. Haiyang 《Sensors and actuators. B, Chemical》2008,134(1):258-265
Six imidazolium-based ionic liquids (ILs) were synthesized and employed as sensing materials coated on quartz crystal microbalance for the detection of organic vapors. Acetone, ethanol, dichloromethane, benzene, toluene and hexane were selected as representatives for common environmental pollutants, and good linear responses from 0 to 100% of concentrations were observed. The halogen-anion-containing imidazolium ILs-coated sensors showed fast response, excellent reversibility, and considerable sensitivity and selectivity towards alcohols, and the selective factors were up to 30 times for ethanol versus other VOCs. The existence of water vapor reduced the frequency response of the sensor, but a good linear relationship remained. 相似文献
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Initial studies into the development of a self-powered controlled release system using ionic liquid electrolyte were performed via galvanic coupling of a conducting polymer doped with dye and a zinc anode. The conducting polymer employed was polypyrrole (PPy) doped with phenol red (PR) dye. The electrochemical properties of the polymer as well as the dye release process initiated by a Zn electrode were investigated. A bilayer conducting polymer structure wherein polypyrrole–polystyrene sulfonate (PPy-PSS) coated on top of PPy-PR ensured no leakage of dye, yet allowed efficient release of PR on galvanic coupling in a temperature sensitive electrolyte. 相似文献
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Eduardo ZappAuthor VitaeDaniela BrondaniAuthor Vitae Iolanda C. VieiraAuthor VitaeCarla W. ScheerenAuthor Vitae Jairton DupontAuthor VitaeAntônio M.J. BarbosaAuthor Vitae Valdir S. FerreiraAuthor Vitae 《Sensors and actuators. B, Chemical》2011,155(1):331-339
This study focuses on the development and evaluation of a new biosensor for the determination of the pesticide methomyl, based on enzyme inhibition. Laccase (LAC) obtained from a genetically modified fungus (Aspergillus oryzae) was successfully immobilized in a new supported ionic liquid phase (SILP) based on platinum nanoparticles and the 1-butyl-3-methylimidazolium tetrafluoroborate ionic liquid (Pt-BMI·BF4) supported in montmorillonite, and subsequently applied in the construction of the biosensor. The process of inhibition by methomyl carbamate was performed using dopamine as a phenolic substrate to obtain the base signal. All measurements for the optimization and application of the biosensor were performed by square-wave voltammetry, and the best experimental conditions were obtained in acetate buffer solution (0.1 mol L−1, pH 5.5), with 0.5 units of enzyme and voltammetric parameters: 60 Hz of frequency, 100 mV of pulse amplitude and 8 mV of scan increment. The determination of methomyl in carrot and tomato samples using the proposed biosensor showed results consistent with those obtained by HPLC, verifying that the method developed can be used for the quantification of this pesticide. 相似文献
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Lin Yaqian Hua Ya Jianfei Guangming Zaisheng Ping Xuxiao Huiping Yunhui 《Sensors and actuators. B, Chemical》2009,142(1):316-320
A novel strategy for the preparation of amperometric immunosensor for rapid determination of α-1-fetoprotein (AFP) in human serum has been developed. TiO2 nanoparticles (NPs) were prepared by solvothermal reaction using TiCl4 as raw materials and the mixture of ionic liquids and doubly distilled water as solvent. α-1-fetoprotein antibody (AFP Ab) was mixed with TiO2 NPs/chitsotan (CHIT) solution and immobilized onto the surface of a glassy carbon electrode. AFP (Ab) functionalized Au NPs were used as catalytic labels for the amperometric detection of AFP by means of the electrocatalyzed reduction of Au NPs to H2O2. The electrochemical behavior of the immunosensor was studied. Other experimental conditions such as pH, immunoreactions temperature and time were also studied. The prepared immunosensor offers an excellent amperometric response for AFP ranging from 1.0 to 160.0 ng/mL with a detection limit of 0.1 ng/mL. The result shows that the immunosensor displays rapid response, high sensitivity, good reproducibility and favorable stability. 相似文献