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61.
In this work, a sensitive, practical and reliable acetylthiocholine (ATCh) biosensor based on poly(allylamine hydrochloride) functionalized multiwalled carbon nanotube (PAH/MWCNT) was fabricated and used for pesticide detection. As far as we know, this is the first work that constitutes the usage of PAH and MWCNT for ATCh biosensor. The developed system was characterized by using scanning electron microscopy, electrochemical impedance spectroscopy and cyclic voltammetry. The influence of parameters such as enzyme amount and pH were examined and a linearity between 5×10?5 M?2.0×10?3 M for ATCh was obtained. The proposed biosensor was applied for a model pesticide, monocrotophos, detection. The analytical curve showed an excellent linearity in the monocrotophos concentration range of 1–25 pg/mL with an incubation time of 5 min. Limit of detection and limit of quantification values were calculated as 0.88 and 2.9 pg/mL, respectively. The system was also applied for detection of monocrotophos in grape, tomatoe, tap and mineralized water samples and promising recovery values were obtained. 相似文献
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A composite electrode was prepared by modifying glassy carbon microparticles with gold nanoparticles (Au-nps) and xanthine oxidase enzyme (XOD) for xanthine (X) and hypoxanthine (Hx) detection. After the optimization of the system for X, the biosensor was characterized for X and Hx. A linearity was obtained in the concentration range between 5.00 × 10−7 and 1.00 × 10−5 M for X with equation of y = 0.24x + 0.712 and 5.00 × 10−6 to 1.50 × 10−4 M for Hx, with equation of y = 0.014x + 0.575, respectively. Obtained results were compared to X and/or Hx biosensors including/not including Au-np in the structure. The developed system was also applied for detection of Hx in canned tuna fish sample and very promising results were obtained. 相似文献
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Shaporenko A Brunnbauer M Terfort A Johansson LS Grunze M Zharnikov M 《Langmuir : the ACS journal of surfaces and colloids》2005,21(10):4370-4375
Self-assembled monolayers (SAMs) formed from 4,4'-terphenyl-substituted alkanethiols C6H5(C6H4)2-(CH2)nSH (TPn, n = 1-6) on polycrystalline (111) gold and silver substrates have been characterized by synchrotron-based high-resolution X-ray photoelectron spectroscopy. The intensities, binding energy positions, and width of most photoemission lines exhibited pronounced odd-even effects, i.e., systematic and periodic variation, depending on either odd or even number of the methylene units in the aliphatic linker of the TPn molecules. The detailed analysis of these effects provides important information on the bonding and arrangement of the chemisorbed sulfur headgroups in the TPn films and balance of the structural forces in alkanethiolate SAMs. 相似文献
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Barkovskii Savelii V. Ulitko Maria V. Barkov Alexey Yu. Kochnev Ivan А. Zimnitskiy Nikolay S. Korotaev Vladislav Yu. Sosnovskikh Vyacheslav Ya. Stepanyuk Roman А. Madzhidov Timur I. 《Chemistry of Heterocyclic Compounds》2022,58(8-9):462-472
Chemistry of Heterocyclic Compounds - A method for a regio- and stereoselective synthesis of N-unsubstituted... 相似文献
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Selective Cell Adhesion and Biosensing Applications of Bio‐Active Block Copolymers Prepared by CuAAC/Thiol‐ene Double Click Reactions 下载免费PDF全文
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A novel type of thrust system is proposed that operates in air and consists of an emitter of charged droplets and a multigrid electrode system in which the stream of these droplets flows in a constant longitudinal electric field, thereby initiating an air flow. The reactive force caused by the air flow and the efficiency with which the electric current energy is converted into the energy of this flow are estimated. It is shown that if a battery of hydrogen fuel elements is used as a power supply, this method of electrical propulsion makes it possible to reduce energy expenditure more than fourfold as compared to existing propeller vehicles. A feasible scheme is presented for a vehicle using such an engine. 相似文献