共查询到20条相似文献,搜索用时 31 毫秒
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Robert L. Metcalf 《Mikrochimica acta》1998,129(3-4):167-180
Chemical ecology of the Insecta comprises an invisible environment where semiochemicals are the principal factors regulating the mating and host-selection of the one million or more species. Biologically effective concentrations of these semiochemicals range from 10–10 to 10–3 g at the insect antennal receptors. These levels are virtually undetectable by conventional microchemistry, and can be measured only by behavioral bioassay and by electrophysiology which are about 10,000 and 100-fold more sensitive than gas chromatography.Despite more than 40 years of study, the sex pheromones have been identified from only about 1300 species of insects (0.1%). The dearth of information about kairomones from host plants for phytophagous insects is even more astonishing, and only about 400 plant species have been studied extensively (ca. 0.2%), and the odorant spectra characterized in only 10 important crop plants. These odorants are chemically complex and their action as semiochemicals for insect herbivores, involves degrees of receptor specificity and synergism that are virtually unstudied.These lacunae in our knowledge of chemical ecology are fundamental to the study of ecology, behavior, and evolution of insects; but also are of vital importance in applied entomology. There is much societal pressure to progress from broadcast application of insecticides, to specific and innovative methods for insect control that are non-hazardous to human health and to environmental quality. Pest management strategies involving the use of semiochemicals are essential to reach this goal. These include monitoring insect populations vis-a-vis the economic threshold, the use of attracticide baits, and strategies for mating confusion and behavioral confusion of insect pest populations in row and orchard crops.The immensity of the semiochemical environments of plant and insect communities, the intellectual challenges for understanding ecology and evolution, and the immediate need for application to applied entomology provide compelling reasons for enhanced study of the microchemistry of semiochemicals. 相似文献
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Recent Advances in Electrochemical Sensors Based on Molecularly Imprinted Polymers and Nanomaterials
This review focuses on the recent achievement during period of 2013–2018 related to the electrochemical sensors based on molecularly imprinted polymers (MIPs) combined with nanomaterials for various kinds of applications. MIPs based electrochemical sensors have found a great interest due to their high stability, short time required for electropolymerization, and high specificity towards the target analyte. The sensitivity is considered as one of the important parameter in electrochemical sensing strategies that should be improved by the combination of highly conductive nanomaterials with selective MIPs. In general, the most employed nanomaterials are magnetic nanoparticles, gold nanoparticles (AuNPs), carbon nanotubes and graphene. This review discusses the main current achievement as well as the current challenges regarding the development of biomimetic sensors in electroanalysis. 相似文献
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Dounia Elfadil Abderrahman Lamaoui Flavio Della Pelle Aziz Amine Dario Compagnone 《Molecules (Basel, Switzerland)》2021,26(15)
Detection of relevant contaminants using screening approaches is a key issue to ensure food safety and respect for the regulatory limits established. Electrochemical sensors present several advantages such as rapidity; ease of use; possibility of on-site analysis and low cost. The lack of selectivity for electrochemical sensors working in complex samples as food may be overcome by coupling them with molecularly imprinted polymers (MIPs). MIPs are synthetic materials that mimic biological receptors and are produced by the polymerization of functional monomers in presence of a target analyte. This paper critically reviews and discusses the recent progress in MIP-based electrochemical sensors for food safety. A brief introduction on MIPs and electrochemical sensors is given; followed by a discussion of the recent achievements for various MIPs-based electrochemical sensors for food contaminants analysis. Both electropolymerization and chemical synthesis of MIP-based electrochemical sensing are discussed as well as the relevant applications of MIPs used in sample preparation and then coupled to electrochemical analysis. Future perspectives and challenges have been eventually given. 相似文献
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Considering the potential bioactivities of natural product and natural product-like compounds with highly complex and diverse structures, the screening of collections and small-molecule libraries for high-throughput screening (HTS) and high-content screening (HCS) has emerged as a powerful tool in the development of novel therapeutic agents. Herein, we review the recent advances in divergent synthetic approaches such as complexity-to-diversity (Ctd) and biomimetic strategies for the generation of structurally complex and diverse indole-based natural product and natural product-like small-molecule libraries. 相似文献
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The increasing importance of biological analytes in chemistry has triggered the development of a vast number of techniques for rapidly assessing them. Aside from microbiological test methods, a wide range of analytical sensor and detection methods are being developed. Within this article, we review the literature on this topic from the last five years, stressing two main aspects of method development. The first aspect is the design of novel analytical strategies and transducers to generate signals more sensitively, more rapidly and more efficiently. Most of the progress in this field has focused on electrochemical detection, although novel approaches to optical and mass-sensitive measurements have been reported. Second, we provide an overview of two main approaches to creating artificial interaction layers for sensors based on tailored interaction sites in polymeric or biomimetic systems. The most prominent of these approaches is (molecular) imprinting, where selectivity is achieved by directly templating a polymer material with the target analyte or a model compound, thus achieving biomimetic interaction sites within both thin films and particles. 相似文献
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Rajpal Singh Dr. Thathan Premkumar Dr. Ji‐Young Shin Kurt E. Geckeler Prof. Dr. Dr. 《Chemistry (Weinheim an der Bergstrasse, Germany)》2010,16(6):1728-1743
Carbon nanotubes constitute a novel class of nanomaterials with potential applications in many areas. The attachment of metal nanoparticles to carbon nanotubes is new way to obtain novel hybrid materials with interesting properties for various applications such as catalysts and gas sensors as well as electronic and magnetic devices. Their unique properties such as excellent electronic properties, a good chemical stability, and a large surface area make carbon nanotubes very useful as a support for gold nanoparticles in many potential applications, ranging from advanced catalytic systems through very sensitive electrochemical sensors and biosensors to highly efficient fuel cells. Here we give an overview on the recent progress in this area by exploring the various synthesis approaches and types of assemblies, in which nanotubes can be decorated with gold nanoparticles and explore the diverse applications of the resulting composites. 相似文献
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Disposable amperometric sensors for hydrazines have been fabricated by a judicious tailoring of the surface of screen-printed electrodes. Strong electrocatalytic action towards the oxidation of hydrazines is achieved by incorporating cobalt phthalocyanine within the carbon inks or by covering the printed surface with a mixed valent ruthenium cyanide coating. The electrocatalytic behavior, sensor optimization and analytical performance are reported. The new sensor strips should facilitate on-site environmental and industrial monitoring of hydrazine compounds. 相似文献
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A portable sensor platform for the detection of small molecular species is crucial for the on-site monitoring of environmental pollutants, food toxicants, and disease-related metabolites. However, it is still extremely difficult to find highly selective and sensitive sensor platforms for general small molecular detection. Herein, we report aptamer sandwich-based carbon nanotube sensor strategy for small molecular detection, where aptamers were utilized to capture target molecules as well as to enhance the sensor signals. We successfully demonstrated the detection of non-polar bisphenol A molecules with a 1 pM sensitivity. Significantly, our sensors were able to distinguish between similar small molecular species with single-carbon-atomic resolution. Furthermore, using the additional biotin modification on labeling aptamer, we enhanced the detection limit of our sensors down to 10 fM. This strategy allowed us to detect non-polar small molecular species using carbon nanotube transistors, thus overcoming the fundamental limitation of field effect transistor-based sensors. Considering the extensive applications of sandwich assay for the detection of rather large biomolecules, our results should open up completely new dimension in small molecular detection technology and should enable a broad range of applications such as environmental protection and food safety. 相似文献
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Sarina M. Berger Matthias Ferger Prof. Dr. Todd B. Marder 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(24):7043-7058
In recent years, research in the fields of optoelectronics, anion sensors and bioimaging agents have been greatly influenced by novel compounds containing triarylborane motifs. Such compounds possess an empty p-orbital at boron which results in useful optical and electronic properties. Such a diversity of applications was not expected when the first triarylborane was reported in 1885. Synthetic approaches to triarylboranes underwent various changes over the following century, some of which are still used in the present day, such as the generally applicable routes developed by Krause et al. in 1922, or by Grisdale et al. in 1972 at Eastman Kodak. Some other developments were not pursued further after their initial reports, such as the synthesis of two triarylboranes bearing three different aromatic groups by Mikhailov et al. in 1958. This review summarizes the development of synthetic approaches to triarylboranes from their first report nearly 135 years ago to the present. 相似文献
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In recent years, various biomimetic materials capable of forming gaseous plastron on their surfaces have been fabricated and widely used in various disciplines and fields. In particular, on submerged surfaces, gaseous plastron has been widely studied for antifouling applications due to its ecological and economic advantages. Gaseous plastron can be formed on the surfaces of various natural living things, including plants, insects, and animals. Gaseous plastron has shown inherent anti-biofouling properties, which has inspired the development of novel theories and strategies toward resisting biofouling formation on different surfaces. In this review, we focused on the research progress of gaseous plastron and its antifouling applications. 相似文献
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This focused review presents various approaches or formats in which liquid crystals (LCs) have been used as stimuli-responsive sensors. In these sensors, the LC molecules adopt some well-defined arrangement based on the sensor composition and the chemistry of the system. The sensor usually consists of a molecule or functionality in the system that engages in some form of specific interaction with the analyte of interest. The presence of analyte brings about the specific interaction, which then triggers an orientational transition of the LC molecules, which is optically discernible via a polarized optical image that shows up as dark or bright, depending on the orientation of the LC molecules in the system (usually a homeotropic or planar arrangement). The various applications of LCs as biosensors for glucose, protein and peptide detection, biomarkers, drug molecules and metabolites are extensively reviewed. The review also presents applications of LC-based sensors in the detection of heavy metals, anionic species, gases, volatile organic compounds (VOCs), toxic substances and in pH monitoring. Additionally discussed are the various ways in which LCs have been used in the field of material science. Specific attention has been given to the sensing mechanism of each sensor and it is important to note that in all cases, LC-based sensing involves some form of orientational transition of the LC molecules in the presence of a given analyte. Finally, the review concludes by giving future perspectives on LC-based sensors. 相似文献
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Xinyu Liu Janusz Pawliszyn 《International journal of environmental analytical chemistry》2013,93(15):1189-1200
A novel device, membrane extraction with a sorbent interface (MESI) coupled with a portable gas chromatograph (GC) system, has been developed. The main components of this system include a membrane module, a microtrap, and a control unit for the heater and cooler. The membrane module, as an on-line sample-introduction device for this system, can be manipulated in different configurations, allowing for the selective permeation of analytes across the membrane into the carrier/stripping gas. The analytes are trapped and concentrated onto a microtrap, which serves as an injector for gas chromatography separation. A concentration pulse of the trapped analytes is generated through direct electrical heating of the microtrap. The characteristics of this system have been explored, and its applicability and effectiveness have been demonstrated in field monitoring applications including the analysis of toluene in wastewater, Volatile organic compounds (VOCs) in laboratory air, and chloroform in swimming-pool water. This system is very promising, as it is a simple, fast, and portable tool for on-site process environmental monitoring. 相似文献
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松毛虫性信息素微量成分鉴定方法的研究 总被引:9,自引:0,他引:9
采用气相色谱-质谱分析确认了顺-5-,反-7-十二碳二烯乙酸酯是思茅松毛虫性信息素腺体的主要成分(次要成分由于含量极微且受杂质干扰,未能获得全扫描质谱图)。利用高分辨率毛细管气相色谱分析了思茅松毛虫性信息素腺体提取物的酯基转移和乙酰化反应的衍生物,进一步确认了顺-5-,反-7-十二碳二烯醇是思茅松毛虫性信息素腺体中的微量成分。探讨了功能团相互转换微量化学反应法鉴定松毛虫性信息素腺体中微量成分功能团和立体构型的优点。强调了性信息素微量成分鉴定工作在昆虫化学通讯系统研究中的重要性。 相似文献
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Nosrat O. Mahmoodi Fateme Ghanbari Pirbasti 《Phosphorus, sulfur, and silicon and the related elements》2016,191(6):811-843
Thiazoles are important heterocyclic compounds which have many biological activities and different applications such as useful ligands, in optical sensors, etc. A literature survey shows that there are different routes to thiazoles. One of the most frequently used synthetic approaches consists of a reaction between α-halocarbonyl compounds with a CSNH2 moiety. In this mini-review we have classified the contents based on the reagent or material providing the sulfur atom of the thiazole ring. Also, among many articles which have been devoted to thiazole syntheses here we presented some synthetic approaches published from 2012 to 2014. 相似文献
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Vesicles are self-assembled nanosized structures that result from the auto-organization of amphiphilic compounds into closed bilayers. These systems are highly attractive subjects of fundamental research owing to their role as biomimetic models of cell membranes and compartmentalization systems. Vesicles also display very interesting features and properties for practical applications, namely as superior nanocontainers for encapsulation of functional molecules and materials. Exerting control over the formation, dissociation and permeability of these containers is therefore of paramount importance for many of their potentials applications. Being light the stimulus of choice for remote spatiotemporal control, we have compiled and revised selected published works on photoresponsive vesicles with the aim of providing an overview of the main strategies, advantages and limitations of such systems. 相似文献
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Mayara Cristina Mombach Lorenz Leandro Silva de Almeida Ana Paula de Oliveira Lopes Inacio Flávio Manoel Rodrigues da Silva Júnior Eliézer Quadro Oreste Daiane Dias 《Electroanalysis》2023,35(7):e202200354
Nowadays, carbon-based materials applied to the development of chemically modified sensors have been highlighted once they can generate methods with high sensitivity, stability, conductivity, accuracy and low cost. Hence, these sensors have been used in environmental monitoring in aneco-friendlyy, sensitive, fast, efficient, inexpensive and robust way. In this review, firstly we described about carbon-based materials and their derivatives, followed by the chemically modified carbon-based sensors manufacturing overview and their applications in environmental analytical chemistry related to inorganic and organic compounds determinations. Future perspectives on trends of the carbon-based materials applications in the sensor modifications are also described. 相似文献
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一类新型主体分子——杯冠化合物 总被引:5,自引:0,他引:5
本文综述了新型主体分子杯冠化合物的研究进展, 讨论了它们的合成、构象、手性性质、超分子识别功能以及作为化学传感器和模拟酶应用等方面的问题。 相似文献