Dually Electroactive Disulfide‐Confined Aryldiazonium Salt Used as a Linker Molecule for Preparing Immunosensor Platforms

A new electroactive disulfide‐confined aryl diazonium (DSAD) salt was synthesized and used as a linker for biomolecules immobilization to prepare two kinds of immunoassay platforms. DSAD was electrodeposited on ITO electrode surfaces by cyclic voltammetry. Disulfide group of DSAD attached on the surfaces were electrochemically oxidized into thiosulfinate or thiosulfonate groups. For the first work, a detection of rabbit antigen was performed on ITO microelectrodes array by spatially‐selective approach. In the second work, DSAD was deposited on electrochemically reduced graphene oxide‐modified ITO surfaces, which were used as a platform for electrochemical sandwich immunoassay for detecting mouse antigen.     

Simultaneous Titration of Ternary Mixtures of Pb(II), Cd(II) and Cu(II) with Potentiometric Electronic Tongue Detection

An automatic titration method is reported to resolve ternary mixtures of transition metals (Pb²⁺, Cd²⁺ and Cu²⁺) employing electronic tongue detection and a reduced number of pre‐defined additions of EDTA titrant. Sensors used were PVC membrane selective electrodes with generic response to heavy‐metals, plus an artificial neural network response model. Detection limits obtained were ca. 1 mg L^?1 for the three target ions and reproducibilities 3.0 % for Pb²⁺, 4.1 % for Cd²⁺ and 5.2 % for Cu²⁺. The system was applied to contaminated soil samples and high accuracy was obtained for the determination of Pb²⁺. In the determination Cd²⁺ and Cu²⁺, sample matrix showed a significant effect.     

DOA estimation for uniform circular array without the source number based on beamspace transform and higher-order cumulant

Fourth-order cumulant is one of most widely used high-order cumulant for direction of arrival (DOA) estimation due to its ability of expanding the virtual array aperture as well as suppressing Gaussian noise. To address the two-dimensional (2D) DOA estimation problem, we propose a modified MUSIC scheme for uniform circular array (UCA) in this paper. Firstly, the fourth-order cumulant of UCA is considered to construct a new propagator, resulting in the elimination of a priori knowledge of the number of signals. Secondly, the UCA is transformed by beamspace transformation, reducing the time computational complexity of the algorithm since the two-dimensional grid search and singular value decomposition are avoided. And finally a low-rank recovery algorithm is adopted to improve the accuracy regarding the limited snapshots scenario. The numerical simulations validate the superiority of the proposed method.     

Supramolecular optical sensor arrays for on-site analytical devices

Supramolecular optical chemosensors are useful tools in analytical chemistry for the visualization of molecular recognition information. One advantage is that they can be utilized for array systems to detect multiple analytes. However, chemosensor arrays have been evaluated mainly in the solution phase, which limits a wide range of practical applications. Thus, appropriate solid support materials such as polymer gels and papers are required to broaden the scope of the application of chemosensors as on-site analytical tools. In this review, we summarize the actual approaches for the fabrication of solid-state chemosensor arrays combined with powerful data processing techniques and portable digital recorders for real-world applications.     

Copper-cobalt-nickel oxide nanowire arrays on copper foams as self-standing anode materials for lithium ion batteries

Numerous scientists are in the pursuit of energy storage materials with high energy and high power density by assembly of electrochemically active materials into conductive scaffolds, owing to the emerging need for next-generation energy storage devices. In this architectures, the active materials bonded to the conductive scaffold can provide a robust and free-standing structure, which is crucial to the fabrication of materials with high gravimetric capacity. Thus, hierarchical copper-cobalt-nickel ternary oxide (CuCoNi-oxide) nanowire arrays grown from copper foam were successfully fabricated as free-standing anode materials for lithium ion batteries (LIBs). CuCoNi-oxide nanowire arrays could provide more active sites owing to the hyperbranched structure, leading to a better specific capacity of 1191 mAh/g, cycle performance of 73% retention in comparison to CuO nanowire structure, which exhibited a specific capacity of 1029 mAh/g and capacity retention of 43%, respectively.     

比色法在爆炸物检测中的研究进展

爆炸物杀伤力大、隐蔽性强,被广泛应用于军事战争,也是恐怖分子施暴方式的首选。基于保护人民生命和财产安全的迫切需求,爆炸物检测技术受到世界公共安全领域的高度重视。相比于其它分析方法,比色法因操作简便、抗干扰性强,不依赖分析设备的优势成为最适用于现场快速检测爆炸物的方法之一。该文主要综述了比色法在爆炸物探测领域的研究进展,包括对比色探针和比色阵列研究进展的总结与前景分析,并重点讨论了比色人工嗅觉系统及其在爆炸物检测中的应用,展望了其未来的发展趋势和应用前景。     

微纳电极阵列检测丘脑底核电刺激引起的纹状体神经元活动变化

丘脑底核(STN)深部脑刺激(DBS)已成为帕金森病的重要外科治疗手段,然而其确切的作用机理尚不明确.本研究采用微机电系统(MEMS)技术制备了一种16通道植入式微电极阵列(MEA),在MEA表面修饰了铂黑-还原氧化石墨烯-Nafion膜(Pt/RGO/Nafion)纳米材料,用于同步检测麻醉大鼠脑内纹状体神经元在STN电刺激前后多巴胺(DA)含量和动作电位(Spike)发放变化.STN-DBS结果表明,电刺激20 s后,DA含量开始升高,最高达1.72 μmol/L,较高浓度状态保持约50 s后回落至正常水平.与此同时, 检测到在DA上升阶段中间神经元Spike发放活动增强,在保持高于DA正常浓度水平阶段,中等多棘神经元(MSNs)放电频率增加.本研究制备的微电极阵列传感器能够实现脑内多巴胺和电生理的原位实时检测,有望成为神经信息检测的有力工具.     

聚多巴胺还原高锰酸钾制备二氧化锰阵列纳米管

以通过水热法在石英玻璃片表面合成的ZnO纳米棒为模板,在其表面生成聚多巴胺薄膜,然后与KMnO4反应,制备了MnO_2阵列纳米管。经表征发现,制备的MnO_2纳米管形态良好,在基底表面的附着力强;所制备的MnO_2为非晶型。由于ZnO模板易合成、易去除、形态好,且聚多巴胺薄膜的生成方法也很简便易行,使得该制备MnO_2纳米管阵列的方法具有简便、快捷、适用性广等的特性,对MnO_2新形态纳米结构的构建具有一定的启示作用。     

Speciation of Arsenic in Drinking Water by Dispersive Liquid–Liquid Microextraction,Graphite Furnace Atomic Absorption Spectrometry,and Orthogonal Array Design

Orthogonal array design was used to optimize arsenic speciation in drinking water in contact with materials by dispersive liquid–liquid microextraction followed by graphite furnace atomic absorption spectrometry. Arsenic speciation was achieved by the formation of an arsenic(III) hydrophobic complex with a new chelating agent, 1,2,6-hexanetriol trithioglycolate, at neutral pH. The complex was extracted into the organic phase, while arsenic(V) remained in aqueous solution. The concentration of As(V) was determined by subtracting As(III) from the total arsenic following the reduction of As(V) to As(III) by L-cysteine. Orthogonal array design with OA₁₆ (44) and OA₉ (33) matrices was used to optimize the efficiency of dispersive liquid–liquid microextraction and the reduction of As(V) to As(III), respectively. Under the optimal conditions, the detection limit was 0.03?µg?L^?1 for As(III) and the relative standard deviation was 5.9% with an enhancement factor of 87. The calibration curve was linear from 0.19 to 3.0?µg?L^?1 with a correlation coefficient of 0.9996. The developed method was used for arsenic speciation in solutions of drinking water that contacted materials. The recoveries of fortified samples were in an acceptable range from 92.0 to 113.3%.