红外反射光谱电化学中薄层电解池效应的研究

用双电位阶跃计时电流法,动电位扫描等电化学技术和红外光谱法系统测定了现场红外镜反射式电解池中的薄层厚度,电化学特性和光谱特性。结果表明,红外光谱电化学研究中的电解池存在定量的薄层电解效应。     

多用途薄层光谱电化学池的设计和表征

设计并组装了一种简易薄层光谱电化学池.该池具有结构简单、操作方便、对工作电极无透光要求,且能适用于多种现场光谱电化学研究的特点.用该池记录了邻联甲苯胺高氯酸醋酸组成的氧化还原体系的荧光光谱电化学和紫外可见光谱电化学响应,并用吡啶氯化钾体系进行了喇曼光谱电化学表征.     

血红蛋白在裸银电极上的光谱电化学研究

光谱电化学作为把光谱技术和电化学方法有机结合起来的一门新技术［１］,已成为将电化学研究提高到分子水平的强有力手段．多种类型及不同用途的光谱电化学池［２］成功地应用于生物分子的电化学及光谱电化学性质研究［３］．我们利用自制的长光程薄层光透光谱电化学池研...     

反射式薄层可见光谱电解池的制作与性能测试

设计制作了一种反射式薄层可见光谱电解池。该电解池采用光亮铂片作为工作电极,将铂丝辅助电极和Ag AgCl参比电极组装在一起。薄层池中间的溶液薄层是通过光亮铂片和覆盖其上的玻璃片之间的塑料薄膜垫圈加以控制,当液层厚度为0.2mm时,液层容积为16μL。由于采用双平行反射的光路,使入射光与出射光保持在一直线上,可以在不变更光路系统下的各种光度计上使用。在K3Fe(CN)6 K4Fe(CN)6体系中,用循环伏安法、恒电位现场光度法进行性能测试。实验结果表明,该电池具有良好的薄层光谱电化学性能,可用于薄层可见光谱电化学研究。     

高温红外光谱电化学薄层池的制作与表征

为了拓宽光谱电化学研究范围,开展高温下电化学反应过程,本文研制了一种高温红外光谱电化学薄层池(HTC)。 研制的HTC清洗方便,操作简单,适用于水体系和有机体系。 该HTC可在室温至373 K(根据溶剂沸点,控温精度为±0.5 K)温度范围内使用,具有良好的电化学性能,红外光谱采集谱图清晰信噪比好。 利用铁氰化钾水溶液和对苯醌离子液体溶液的红外光谱电化学行为对HTC进行了表征,得到较满意的结果。     

四硝基酞菁锌配合物的光谱电化学性质

带有各种取代基的酞菁配合物虽已有研究,但有关硝基酞菁锌配合物在溶液中的氧化还原产物研究尚未见报道.本文用薄层光谱电化学技术对该配合物的电解产物进行了研究. 1 实验部分 HDP-1型恒电位仪;F-78型脉冲极谱仪;UV-240型紫外可见分光光度计.四硝基酞菁锌(ZnTNPc)按文献合成和提纯.电化学实验在氮气中于三电极电解池中进行,工作电极(0.001cm~2)、辅助电极均为铂丝,银丝为参比电极,二茂铁作内参比物.支持电解质为0.1mol/L TBAP,ZnTNPc浓度为1.0×10~(-5)mol/L.光谱电化学实验方法见文献,电解液为0.3mol/L TBAP和1.0×10~(-4)mol/L ZnTNPc.     

用于现场FTIR及UV/Vis光谱电化学的高质量简单结构的光透薄层电化学池

设计制作了一种应用于紫外可见、红外电谱电化学的新型光透薄层电化学池(OTTLE),并以铁氰化钾水溶液、二茂铁乙腈溶液体系进行了表征。池腔几何结构的合理设计使电位降和边缘效应降至最低。该池有良好的伏安响应特性并可用它得到高质量的UV/Vis和IR光谱。由于简单的结构及低廉的造价使适用于光谱电化学研究的电化学池变得更容易得到。     

酞菁铑的合成及其性质研究

本文合成了铑(Ⅲ)酞菁配合物,用循环伏安法研究了该配合物在二甲基甲酰胺、吡啶和二甲亚砜等有机溶剂中的电化学,并利用薄层透光电极电解;获得了该配合物四种不同氧化态时的电子光谱,并对电极反应机理及其产物进行了讨论.     

核黄素的薄层荧光光谱电化学研究

光谱检测技术和电化学手段密切结合起来的光谱电化学方法,加上薄层池的整体快速电解,已成为化学工作者的重要研究手段［１］．目前紫外可见透射光谱检测方法多采用铂、金、石墨等的网栅为工作电极,对其透光度及强度均有一定要求,操作不便,池也不易清洗［２］;并且由...     

反射薄层光谱电化学方法的应用

用自行设计的反射光谱薄层电解池测定了二茂铁在NaClO_1/CH_3CN中的E~O′和n值、铁氰化钾在KCl底液中和亚甲蓝在KNO_3/DMSO中的扩散系数。对亚甲蓝在二甲亚砜介质中的还原过程进行了研究,证明有一电子还原产物存在。     

毛细管超薄池光度吸附测量新技术

在毛细管超薄池光度检测中首次采用吸收光强测量新技术,显著提高了测量的灵敏度和改善了信噪比。在内径50μm的石英毛细管超薄池以及由石英光导纤维构成的十字交叉超薄光学吸收池上,分别测量了系列高锰酸钾溶液吸收光强。吸收光强与高锰酸钾溶液浓度之间呈现良好的线性关系。对于10μg/mL的高锰酸钾稀溶液,毛细管超薄池吸收光强测量的信噪比相对于吸光度测量的有较大的改善。十字交叉池的光程约为40μm,容积约为0.02μL,具有较大的光能量,可望发展成为一种新型的电泳光度检测池。     

新型非线性光学材料的分子设计: 系列螺旋共轭化合物的结构、光谱及二 阶非 线性光学性质的理论研究

采用AM1和ZINDO系列方法研究了螺旋共轭分子2,2'-螺二茚-1,1',3,3'-四酮及其腈基衍生物的几何构型,研究了各分子的稳定构型,并以稳定为基础,计算了这些分子的电子光谱,二阶非线性光学系数βμ,β0,及电荷转移,考察了取代基变化对βμ的影响,计算结果表明所设计分子兼具较大的二阶非线性光学系数和较高的透过率,有希望成为一类新型的二阶非线性光学材料。     

An automatic and quantitative on-chip cell migration assay using self-assembled monolayers combined with real-time cellular impedance sensing

Cell migration is crucial in many physiological and pathological processes including embryonic development, immune response and cancer metastasis. Traditional methods for cell migration detection such as wound healing assay usually involve physical scraping of a cell monolayer followed by an optical observation of cell movement. However, these methods require hand-operation with low repeatability. Moreover, it's a qualitative observation not a quantitative measurement, which is hard to scale up to a high-throughput manner. In this article, a novel and reliable on-chip cell migration detection method integrating surface chemical modification of gold electrodes using self-assembled monolayers (SAMs) and real-time cellular impedance sensing is presented. The SAMs are used to inhibit cell adherence forming an area devoid of cells, which could effectively mimic wounds in a cell monolayer. After a DC electrical signal was applied, the SAMs were desorbed from the electrodes and cells started to migrate. The process of cell migration was monitored by real-time impedance sensing. This demonstrates the first occurrence of integrating cellular impedance sensing and wound-forming with SAMs, which makes cell migration assay being real-time, quantitative and fully automatic. We believe this method could be used for high-throughput anti-migratory drug screening and drug discovery.     

掺锡三氧化二铟导电玻璃双工作电极薄层光透电化学池的设计

本文报道了ITO导电玻璃双工作电极薄层光透电化学池的设计。这种薄层池具有操作简便,成本低廉的特点,其突出优点在于工作电极的边际效应因采用辅助工作电极而得以明显消除。以Fe(CN)_6~(3-)/(4-)~考察了该池的电化学和光谱吸收响应特性。     

新型复合环氧光学树脂的制备与性能研究

通过2,2-二巯基乙硫醚(MES)与环氧氯丙烷反应合成了2,2-二巯基二乙硫醚二缩水甘油醚型环氧树脂(DGEMES),通过FTIR和MS对其进行表征;用乙二胺作为固化剂,将DGEMES与双酚A型环氧树脂(DGEBA)复合固化,得到了新型高折射率和低色散的光学树脂.DGEMES是一种较好的共聚单体,可以同时提高共聚树脂的折射率和阿贝数;DGEBA/DGEMES/乙二胺共固化树脂的nd=1.59～1.62,νd=35～39;当DGEMES的质量分数为40%时,固化树脂的折射率达到1.60以上,冲击强度22.5kJ/m₂,且其它性能较均衡.此外,以甲基六氢苯酐(B-650)为固化剂,还合成了具有中等折射率的DGEBA/DGEMES/B-650共固化树脂(nd=1.54～1.56,νd=38～40),并对其光学和机械性能进行了研究.     

A versatile total internal reflection photometric detection cell for flow analysis

A total internal reflection (TIR) flow-through cell that is highly tolerant of schlieren effects, has limited hydrodynamic dispersion and does not trap gas bubbles, and which is suitable for sensitive photometric measurements in flow analysis, is described. Light from an optical fibre is introduced into a short length of quartz capillary through the sidewall at an incident angle of ca. 53°. Under this condition, incident light undergoes total internal reflection from the external air-quartz interface and is propagated by successive reflections from the external walls through the aqueous liquid core of the cell. Detection of the transmitted beam is enabled by intentionally introducing an optical coupling medium at a predetermined distance along the capillary wall, which allows the internally reflected light to be captured by a second optical fibre connected to a charge-couple device detector.This configuration embodies a number of the desirable features of a liquid core waveguide cell (i.e. total internal reflection), a multi-reflection (MR) flow cell (i.e. minimum susceptibility to schlieren effects, low hydrodynamic dispersion and little tendency to trap bubbles), and a conventional Z-cell (wide dynamic range). When employed with a flow injection system, a limit of detection of 2.0 μg PL⁻¹ was achieved for the determination of reactive phosphate using the TIR cell, compared with LOD values of 3.8 μg PL⁻¹ and 4.9 μg PL⁻¹ obtained using the MR and Z-cells with same manifold.The combined advantages of schlieren-tolerance and lack of bubble entrapment of the MR cell with the higher S/N ratio and wider dynamic range of a conventional Z-cell, make the TIR cell eminently useful for photometric measurements of samples with widely differing refractive indices.     

Flow cell within an LED: a proposal for an optical absorption detector

Droplets formed at the tip of a tube under the same conditions possess extreme uniformity of form, volume and weight. These properties of liquid drop formation have been known for a long time and consequently many applications for the drop have been found in instrumentation and chemical analysis methods. In the present paper, we report on the analytical use of a dynamic LED-based flow-through optical absorption detector with optical path length controlled by continuous dropping of a solution. This arrangement consists of a flow cell built within a high-intensity red LED (λ _max = 630 nm). The feasibility of the detector is demonstrated by colorimetric determination of methylene blue, and ammonium by Berthelot’s reaction, in a flow-injection system. For ammonium, the reaction forms a blue dye (indophenol) with a maximum absorption at 630–650 nm. The detection limit, considered as 3 times the signal of the blank, is better than 125 μg l^-1. The small flow cell represents a good combination of optical path length, low volume and fast washout. This detector can be used advantageously in automated methods and can represent a solution to problems of optical detection involving gas bubbles and precipitation of particles in turbidimetric applications.     

Nanosensing at the single cell level

This article presents an overview of the development, operation, and applications of optical nanobiosensors for use in in vivo detection of biotargets in individual living cells. The nanobiosensors are equipped with immobilized bioreceptor probes (e.g., antibodies, enzyme substrate) selective to specific molecular targets. Laser excitation is transmitted into the fiber producing an evanescent field at the tip of the fiber in order to excite target molecules bound to the bioreceptors immobilized at the fiber tips. A photometric system detects the optical signal (e.g., fluorescence) originated from the analyte molecules or from the analyte–bioreceptor reaction. Examples of detection of biospecies and molecular signaling pathways of apoptosis in a living cell are discussed to illustrate the potential of the nanobiosensor technology for single cell analysis.