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 …

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后,该 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。     

ITO膜薄层光透电化学池的研制

本文描述了以反应蒸发技术制备的高质量铟-锡氧化物(ITO)膜制备薄层光透电化学池的方法,并对其性能进行了测试。结果表明其透光性良好,方块电阻较小,且电位适用范围宽。对邻联甲苯胺体系电化学参数n、E°＇的测定结果与金网薄层电化学池所得结果相符。     

电化学原位拉曼光谱的应用及进展

常规电化学研究方法是以电信号为激励和检测手段,它提供的是电化学体系的各种微观信息的总和,难以准确地鉴别复杂体系的各反应物、中间物和产物,并解释电化学反应机理．近年来,由谱学方法（以光为激励和检测手段）与常规电化学方法相结合产生的谱学电化学技术得到迅速...     

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.     

新型透射式红外光谱电化学池

本文报道一种新型透射式红外光谱电化学池的设计制作。应用盐片加工技术,采用内参比点设置等方法。使该池达到30μm的厚度,且具有十分良好的电化学性能。     

固/液界面现场光谱电化学

固/液界面现场光谱电化学的方法包括各种电磁波透射和反射谱(紫外可见、拉曼、红外、X-光等)、磁共振谱(ESR、NMR)以及80年代发展起来的扫描显微谱(STM等)和非线性反射光谱(SHG)等等。固/液界面现场光谱电化学已渗透到固/液界面和电极表面结构,分子水平上的吸脱附和反应机理,电催化和反应动力学等许多研究领域。本文结合文献对上述几个方面以及固/液界面现场光谱电化学的发展方向进行综述。     

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...     

直立式光透金网电极薄层红外光谱电化学池的新设计

本文报告一种新式的光透式金网电极薄层红外光谱电化学池设计, 该设计使用聚甲氟乙烯池内盐桥/边际限制器, 连接直立式玻璃池体与氯化钠红外薄层池,设置薄层的池的电位参比点, 既便于监控操作, 又能得到良好的光谱电化学响应, 以二茂铁在二氯甲烷中的行为进行了表征。     

光电化学传感器的研究进展

光电化学传感器以光作为激发源,以光电流或光电压作为检测信号,具有响应快速、灵敏度高、设备简单等特点,目前已在环境、食品、医学等多个领域的分析测试中得到广泛应用。该文阐述了光电转换材料与光电化学传感器的制备方法,介绍了光电化学传感器的原理和分类。光电化学传感器包含光寻址电位型传感器和电流型光电化学传感器,其中,电流型光电化学传感器由于优良的光电性能、检出限低、所需材料低廉且易加工等优势而被广泛应用。文中着重介绍了电流型光电化学传感器在金属离子、有机污染物、核酸、蛋白质、细胞等方面的应用,并对光电化学传感器的发展前景进行了展望。     

电化学沉积ZnS@CdS构建光电化学传感器测定谷胱甘肽

采用电化学沉积方法制备了具有核/壳结构的ZnS@CdS复合纳米修饰电极,采用扫描电子显微镜、电化学阻抗谱及光电化学方法对其进行了表征。由于快速有效的电子跃迁和光致电子-空穴对复合的抑制,ZnS@CdS修饰电极的光电流增强。以谷胱甘肽（GSH）为模型,制备了光电化学生物传感器。方法检出限为43 nmol/L,检测范围0.1～60μmol/L。方法已用于葡萄糖注射液中加标回收检测谷胱甘肽的含量,回收率为96.0%～106.5%。     

Capillary size exclusion chromatography with picogram sensitivity for analysis of monoclonal antibodies purified from harvested cell culture fluid

Size exclusion chromatography (SEC) is widely used in the characterization and quality control of therapeutic proteins to detect aggregates. Aggregation is a carefully monitored quality attribute from the earliest stages of clinical development owing to the possibility of eliciting an immunogenic response in the patient. During early stage molecule assessment for cell culture production, small-scale screening experiments are performed to permit rapid turn-around of results so as to not delay timelines. We report the development of a capillary SEC methodology for preliminary molecule assessment to support the evaluation of therapeutic candidates at an early stage of development. By making several key modifications to a commercially available liquid chromatography system, we demonstrate a platform process to perform capillary SEC with excellent precision, picogram sensitivity and good ruggedness. The limit of quantitation was determined to be approximately 15 pg; picogram sensitivity for SEC analysis of monoclonal antibodies had not been achieved prior to this work. In addition, we have developed a method to capture low levels of antibody (1 μg/mL) from harvested cell culture fluid (HCCF) for capillary SEC analysis. Up to 40% recovery efficiency was achieved using this micro-recovery method on 3 mL HCCF samples. Using early stage cell culture transient transfection samples, which typically have much lower titers than stable cell line samples, we demonstrate a consistent method for analyzing aggregates in low protein concentration HCCF samples for molecule assessment and early stage candidate screening.     

Semi-micro size-exclusion chromatography: Molecular-weight measurement of poly (ethylene terephthalate) and separation of oligomers and prepolymers

Summary Several polystyrene gels of different pore sizes were packed into a 500 mm×2.1 mm I.D. column. Semi-micro size-exclusion chromatography (SEC) using these columns was carried out with a system consisting of a triple piston pump, a micro loop injector and a flow cell with 1.0-μl cell volume constructed for semi-micro HPLC, because the dead volume of the injector and the cell volume of flow cell for conventional HPLC caused a significant loss in column efficiency. The effects of sample amount, injection volume and mobile phase flow rate on column efficiency and retention volume were examined and the optimized operational variables of the sample amount (below 500 μg), the injection volume (less than 15 μl) and the flow rate range (30–70 μl/min) determiend for semi-micro SEC. Oligostyrene, epoxy resin, phenol-formaldehyde resin and phthalates were analyzed by the optimized semi-micro SEC system under the given conditions. In addition, molecular weight distribution of four different poly(ethylene terephthalate) films was successfully measured by using a mixture of chloroform and hexafluoroisopropanol as the eluent.     

SEC1酶免疫电极免疫反应的AFM和电化学方法研究

将一种肠毒素抗体共价耦联于自组装的金电极表面 ,利用原子力显微镜识别抗原抗体在多种实验条件下的形貌并通过统计数据进行定量分析 .用作控制实验的是非特异性牛血清白蛋白(BSA)抗原以及低浓度的SEC1抗原 .另外 ,酸性溶液可以打破抗原与抗体之间的结合从而使得生物电极可以被重复使用 .电化学实验支持了AFM的测试结果     

Off-line size-exclusion chromatographic fractionation-matrix-assisted laser desorption ionization time-of-flight mass spectrometry for polymer characterization. Theoretical and experimental study

The parameters affecting the fractionation performance in size-exclusion chromatography (SEC) of broad polymer samples were investigated. Some equations were derived which enable the prediction of polydispersity (PD) in an SEC fraction. Good agreements were obtained between the calculated data and the experimental values. Based on these equations, SEC fractionation conditions were optimized. In the off-line SEC-matrix-assisted laser desorption ionization (MALDI) time-of-flight (TOF) mass spectrometry (MS), two different modes can be employed, i.e., using MALDI-MS to provide an absolute calibration curve for SEC, or using SEC as a sample preparation step for MALDI-MS measurements. It was demonstrated that it is more reliable to use the latter combination, because most problems inherent in SEC can be circumvented. Some guidelines for the optimization of off-line SEC fractionation-MALDI-TOF-MS were given. It was found that under optimized conditions normally only a few SEC fractions are already sufficient to separate a highly polydisperse sample into portions of low PD that can accurately be measured by MALDI-TOF-MS.     

Improved performance of protein separation by continuous annular chromatography in the size-exclusion mode.

In size-exclusion chromatography (SEC), proteins and peptides are separated according to their molecular size in solution. SEC is especially useful as an effective fractionation step to separate a vast amount of impurities from the components of interest and/or as final step for the separation of purified proteins from their aggregates, in a so-called polishing step. However, the throughput in SEC is low compared to other chromatographic processes as good resolution can be achieved only with a limited feed volume (i.e., maximal approximately 5% of the column volume can be loaded). This limitation opposed widespread application of conventional SEC in industry despite its excellent separation potential. Therefore a continuous separation process (namely preparative continuous annular chromatography) was developed and compared to a conventional SEC system both using Superdex 200 prep grade as sorbent. An immunoglobulin G sample with a high content of aggregates was chosen as a model protein solution. The influence of the feed flow-rate, eluent flow-rate and rotation rate on the separation efficiency was investigated. The height equivalent to a theoretical plate was lower for preparative continuous annular chromatography which could be explained by reduced extra column band broadening. The packing quality was proved to be identical for both systems. The productivity of conventional batch SEC was lower compared to continuous SEC, consequently buffer consumption was higher in batch mode.     

以单分散交联聚甲基丙烯酸环氧丙酯树脂为基质的亲水性排阻色谱固定相的合成及其在生物大分子分离中的应用

以单分散交联聚甲基丙烯酸环氧丙酯树脂为基质,将该树脂经化学改性后得到亲水性良好的新型尺寸排阻色谱固定相,其表面羟基含量高达6．1mmol／g。详细评价了该改性后树脂对蛋白的质量回收率、亲水性、耐压性能及化学稳定性。用三羟甲基胺基甲烷(Tris)缓冲溶液(pH=7)为流动相,对蛋白质混合样的分离遵循体积排阻色谱分离机理。     

Spectroelectrochemistry for studying electrochemiluminescence mechanism

UV–Vis spectroelectrochemistry (SEC) was introduced for the first time into the study of electrochemiluminescence (ECL) mechanisms of nitrogen heterocyclic compounds. Uracil and its two derivatives, 5-fluorouracil and 1-methyl-uracil, were chosen as model molecules in the ECL mechanism study. SEC revealed that the substitution of hydrogen at N(1) and the destruction of conjugate heterocyclic ring were very important for ECL activities of uracils. On the basis, a new ECL mechanism was proposed for the uracils. The successful explanation of ECL mechanism for the model molecules by employing SEC indicates that SEC would play an important role in future ECL mechanism studies.     

以氯甲基聚苯乙烯为基质的新型排阻色谱固定相的合成及在生物大分子分离中的应用

以单分散交联聚氯甲基苯乙烯为基质,先后与乙二胺和δ－葡萄糖酸内酯反应,得到了亲水性能良好的排阻色谱固定相,其表面羟基含量高达５．４ｍｍｏｌ／ｇ。本文评价了改性后树脂的亲水性、溶剂匹配性、耐压性能及化学稳定性,用三羟甲基氨基甲烷（Ｔｒｉｓ）缓冲溶液（ｐＨ＝７．０）为流动相,蛋白质,混合样的分离遵循排阻色谱分离机理。聚苯乙烯和蛋白质标准样的排阻色谱分离机理。聚苯乙烯和蛋白质标准样的排阻色谱校正曲线 范     

Radical polymerization in the presence of peroxide and reducing agent monomer for branched polymers

In this article, we report the radical polymerization in the presence of peroxide and commercially available or designed reducing agent monomer (RAM) for the preparation of branched poly(methyl methacrylate)s (PMMAs). The reaction behavior of the RAM was studied by NMR. Triple‐detection SEC (TD‐SEC) analysis was used to confirm the branching structure of the prepared PMMAs and to investigate the influence of peroxide concentration and RAM concentration on molecular weight and branched structure. The obtained branched PMMAs exhibited high molecular weights and relatively narrow polydispersities at high conversion of MMA. Interestingly, a significant increase in molecular weight and degree of branching of the obtained polymers are observed in higher BPO concentration, these results are quite different from that reported in the literature. The unique radical polymerization mechanism in the RAM/BPO redox‐initiated radical polymerization system resulted in branched PMMAs with high molecular weights at relatively high RAM and BPO concentrations. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 833–840