电化学传感器在食品分析中的应用进展

电化学传感器具有操作简便、成本低、检测周期短、灵敏度高、可实时检测等诸多优点,因而在食品分析领域得到广泛的应用。综述了近年来电化学传感器在食品添加剂、食品成分及有害物质检测中的应用,并且指出了目前研究中需要解决的问题并展望了未来发展方向。     

二硫化钼基纳米材料在电化学传感/析氢领域的研究进展

作为一种新兴的二维层状过渡金属二硫化物纳米材料,二硫化钼(MoS2)纳米片具有典型的类石墨烯结构,同时,MoS2拥有极佳的电学、光学和热力学性能以及大的比表面积。这些优异性能使得MoS2在电化学传感和电化学析氢领域具有极大的潜在应用价值。近年来,对MoS2在上述两个电化学领域的研究已经受到了广泛关注,并取得了许多重大进展。在本文中,主要综述了近年来MoS 2在疾病诊断、食品、药物以及环境领域的电化学分析研究进展及通过耦合其他纳米材料在电化学析氢领域的研究进展。     

谈纳米材料修饰电极在生物电化学中的应用

纳米材料具有独特的催化活性和生物兼容性,发展纳米修饰电极,为生命科学提供有价值的检测手段。本文介绍了纳米材料及其性质,对纳米材料修饰电极在生物电化学中的应用做了重点探讨。     

纳米材料过氧化物模拟酶在比色分析及电化学传感器中的应用

纳米材料模拟酶与天然酶相比,稳定性好,反应活性较高,易于对各类功能分子或蛋白质等进行修饰和标记,能够方便地应用于生物分析检测中.近几年,国内外的研究人员制备出各种各样的新型纳米材料模拟酶用于过氧化氢、葡萄糖、癌症标志物的检测.简要总结了近年来国内外磁性纳米粒子、金属纳米粒子、纳米合金等纳米材料模拟酶在比色分析及电化学传感器中应用的研究进展.     

分子印迹技术在电化学中的应用

分子印迹技术是一种对目标分子进行特异性识别的新技术。分子印迹聚合物具有制备方法简单、稳定性好、识别能力强等特点,这些特点使其在膜分离、固相萃取、传感器、催化等方面有了广泛的应用。总结归纳了分子印迹技术的主要特点、分子印迹电化学传感器的制备方法和类别,并对未来发展趋势进行了展望。     

红外光谱法在金属氧化物纳米材料研究中的应用

红外光谱法是材料研究中的一种重要的分析手段.综述了红外光谱法在金属氧化物纳米材料的制备、表征、计算机模拟等方面的应用.在此基础上,指出了红外光谱法在金属氧化物纳米材料中应用的发展方向.     

纳米材料在SPR生物传感器中的应用进展

目的研究纳米材料在SPR生物传感器中的应用进展。方法介绍表面等离子共振(SPR)原理和近几年来纳米材料在SPR生物传感器中的应用研究现状,并重点综述常见的几种纳米材料(包括金纳米粒子、金纳米棒、银纳米粒子、磁纳米粒子、石墨烯和量子点)在SPR生物传感器中的应用新进展。结果 SPR生物传感器是对表面折射率变化敏感的一项分析技术,然而,传统的SPR传感器无法检测极小的折射率变化,这就阻碍了其在超灵敏检测中的应用。结论采用纳米材料提高SPR检测灵敏度和特异性是SPR技术发展的必然趋势。     

量子点的特性及其在分析检测中的应用研究进展

综述量子点的光学特性,胶体合成法、反胶团合成法、溶胶-凝胶法等制备方法,以及在离子传感器和有机小分子传感器等领域中的应用。提出大多数量子点传感器都是基于光致发光猝灭的,实际应用时不够准确,阻碍传感器标准化。认为核-壳结构的量子点能减少一些由重金属组成的常规核芯材料的潜在毒性,有必要建立标准化和系统化的方法,以评估量子点的特定材料的安全性。     

基于碳纳米材料的肾上腺素电化学传感器研究进展

肾上腺素(AD)作为一种神经递质在人体内扮演重要角色,其含量的高低直接影响人体身体健康,因此对AD进行快速检测具有重要的实际意义。其检测方法中电化学方法具有灵敏度高、检测速度快、操作简便的优点,因而构建性能优异的肾上腺素电化学传感器成为研究热点。为提高传感器的电化学性能,碳纳米材料被采纳作为修饰传感器的新型材料而广泛应用,取得了检测限低、灵敏度高并有希望应用于临床检测的巨大进步。本文从碳点、石墨烯、碳纳米颗粒等碳纳米材料出发,分析AD在电极表面的电氧化还原机制,对近年来基于碳纳米材料的肾上腺素电化学传感器制备方法及检测结果进行分类统计,并对今后的检测提出展望,以期获得更有效的肾上腺素电化学传感器。     

一维纳米材料的电化学制备及应用研究

综述了阳极氧化模板法、恒电位电沉积法、脉冲电沉积法制备一维纳米材料的机理,讨论了纳米材料的成核与生长的热力学和动力学,并结合电化学合成方法目前的应用和研究进展展望了一维纳米材料的电化学合成的前景.     

基于MXene的电化学传感研究进展EI北大核心CSCD

MXene是一种早期过渡金属碳化物、氮化物或碳氮化物组成的二维(2D)层状材料。由于MXene具有独特的层状形态、高电导率、高比表面积、优异的亲水性和良好的热稳定性等特性,在物理、化学和纳米技术领域具有广阔的应用前景,可应用于催化、储能和传感器等多种科学领域。本文主要综述基于MXene的电化学传感器的研究进展,介绍电化学传感器的原理、构成,传感界面修饰和MXene制备方法,着重讨论MXene在电化学酶传感器、电化学非酶传感器、电化学免疫传感器、电化学适体传感器和电化学分子印迹传感器方面的研究进展,指出MXene电化学传感领域工业化和商业化利用不足、新种类MXene开发的挑战,对其在各类分析物检测、更多潜在领域的应用进行展望。     

纳米红外吸波材料的研究进展

红外吸波材料在现代隐身技术、节能、绝热等领域具有广泛的应用.扼要介绍了纳米材料的红外吸收机制和红外吸波特点,综述了纳米技术在红外吸波材料中的研究和应用现状.     

Trace detection and discrimination of explosives using electrochemical potentiometric gas sensors

In this article, selective and sensitive detection of trace amounts of pentaerythritol tetranitrate (PETN), 2,4,6-trinitrotoluene (TNT) and cyclotrimethylenetrinitramine (RDX) is demonstrated. The screening system is based on a sampling/concentrator front end and electrochemical potentiometric gas sensors as the detector. Preferential hydrocarbon and nitrogen oxide(s) mixed potential sensors based on lanthanum strontium chromite and Pt electrodes with yttria stabilized zirconia (YSZ) solid electrolyte were used to capture the signature of the explosives. Quantitative measurements based on hydrocarbon and nitrogen oxide sensor responses indicated that the detector sensitivity scaled proportionally with the mass of the explosives (1-3 μg). Moreover, the results showed that PETN, TNT, and RDX samples could be discriminated from each other by calculating the ratio of nitrogen oxides to hydrocarbon integrated area under the peak. Further, the use of front-end technology to collect and concentrate the high explosive (HE) vapors make intrinsically low vapor pressure of the HE less of an obstacle for detection while ensuring higher sensitivity levels. In addition, the ability to use multiple sensors each tuned to basic chemical structures (e.g., nitro, amino, peroxide, and hydrocarbon groups) in HE materials will permit the construction of low-cost detector systems for screening a wide spectrum of explosives with lower false positives than present-day technologies.     

二维纳米材料在腐蚀防护中的应用研究进展

石墨烯薄膜、石墨烯基复合涂料、六方氮化硼、二硫化钼等二维纳米材料具有良好的抗渗透性,在腐蚀防护领域有着广阔的应用前景。首先,概述单层和多层石墨烯涂层的制备方法、防腐机理、实际存在的问题及改进方法;随后,在石墨烯基复合涂料方面,主要探讨石墨烯和氧化石墨烯的各种共价或非共价改性方法及其在有机涂料中的腐蚀防护机制;此外,介绍六方氮化硼和其他二维纳米材料作为新型耐腐蚀材料的主要研究成果;最后,对二维纳米材料在腐蚀防护领域的研究前景进行展望。     

Hydrogen sensing by enzyme-catalyzed electrochemical detection

Hydrogen (H2) is a possible future alternative to current fossil-based transportation fuels; however, its lower explosive limit in air requires a reliable sensor to detect leaks wherever H2 is produced, stored, or used. Most current H2 sensors employ palladium or its alloy as the sensing element, featuring high operating temperature and limited selectivity. In this study, we report using soluble hydrogenase (SH) of aerobic beta-proteobacterium Ralstonia eutropha strain H16 to accomplish ambient, electrochemical detection of H2. Gas samples were collected in a solution containing SH that catalyzed the oxidation of H2. The electrons released during the H2 oxidation reaction were accepted by benzyl viologen (BV2+). The product of the redox reaction, BV+, was then detected using chronoamperometry. Using this sensing scheme, we demonstrate detection of H2 ranging from 1 to 100%. In addition, enzyme kinetics and the effect of oxygen on signal response were studied. Our results indicate that it is feasible to develop a sensor to detect H2 in the atmosphere that is based on enzyme-catalyzed electrochemical detection.     

Application of photoassisted electrochemical detection to explosive-containing environmental samples

High-performance liquid chromatography (HPLC) with ultraviolet (UV) absorbance and photoassisted electrochemical detection (PAED) is applied to the determination of explosives in groundwater and soil samples. On-line, solid-phase extraction minimizes sample pretreatment, enabling direct analysis of groundwater samples and soil extracts. Soils are extracted using pressurized fluid extraction, which is compared to the Environmental Protection Agency (EPA) sonication method. Limits of detection for explosives in the matrixes of interest are equivalent or superior (i.e., <10 parts-per-trillion for HMX) to those achieved using the EPA method 8330. HPLC-UV-PAED is also shown here to be more broadly applicable, as it is capable of determining nitro compounds of interest (e.g., nitroglycerin) that have poor UV chromophores. Additional selectivity of amine-substituted nitroaromatic explosives is achieved by using a photochemical reactor with a 366-nm wavelength lamp. By coupling reversed-phase columns of different selectivities together, baseline resolution of all 14 standard explosives is demonstrated.     

Local electrical potential detection of DNA by nanowire-nanopore sensors

Nanopores could potentially be used to perform single-molecule DNA sequencing at low cost and with high throughput. Although single base resolution and differentiation have been demonstrated with nanopores using ionic current measurements, direct sequencing has not been achieved because of the difficulties in recording very small (～pA) ionic currents at a bandwidth consistent with fast translocation speeds. Here, we show that solid-state nanopores can be combined with silicon nanowire field-effect transistors to create sensors in which detection is localized and self-aligned at the nanopore. Well-defined field-effect transistor signals associated with DNA translocation are recorded when an ionic strength gradient is imposed across the nanopores. Measurements and modelling show that field-effect transistor signals are generated by highly localized changes in the electrical potential during DNA translocation, and that nanowire-nanopore sensors could enable large-scale integration with a high intrinsic bandwidth.     

Application of diamond microelectrodes for end-column electrochemical detection in capillary electrophoresis

Highly boron-doped diamond microelectrodes were employed in an end-column electrochemical detector for capillary electrophoresis (CE). The diamond microline electrodes were fabricated from conducting diamond thin films (exposed surface area, 300 x 50 microm), and their analytical performance as CE detectors was evaluated in a laboratory-made CE installation. The CE-ED system exhibited high separation efficiency for the detection of several catecholamines, including dopamine (DA), norepinephrine (NE), and epinephrine (E), with excellent analytical performance, for example, 155,000 theoretical plates for DA. The diamond-based electrochemical detection system also displayed low detection limits (approximately 20 nM for E at S/N = 3) and a highly reproducible current response with 10 repetitive injections of mixed analytes containing DA, NE, and E (each 50 microM), with relative standard deviations (RSD) of approximately 5%. The performance of the diamond detector in CE was also evaluated in the detection of chlorinated phenols (CP). When compared to the carbon fiber microelectrode, the diamond electrode exhibited lower detection limits in an end-column CE detection resulting from very low noise levels and highly reproducible analyses without electrode polishing due to analyte fouling, which makes it possible to perform easier and more stable CE analysis.