Raman Spectroelectrochemical Study on Bioactive Molecules

本文概述了采用电化学现场拉曼光谱技术研究氧化物歧化酶在L 半胱氨酸修饰金电极表面的电子迁移反应以及腺嘌呤共存条件下超氧化物歧化酶在金电极表面的电子迁移反应和不同电位下银电极表面烟酰胺腺嘌呤二核苷酸的吸附等体系的反应吸附特性 .所得结果对于分析和研究生物活性分子电化学过程机理具有重要意义 .Electron?transfer reaction is known to be one of the key reactions for generating biological functions. Mechanism revelation at a molecular level of such kind reactions is to be very helpful for us to understand life essence. In fact, surface enhanced Raman scattering (SERS) is one of the most powerful tools for the study on metal?electrolyte and metal?vacuum interfaces since 1970's. Moreover, Raman spectroscopic study in enzymology has provided attractive results during last twenty?five years. For the study of electron?transfer reaction mechanism of some oxidoreductases and SERS of some other biological macromolecules, an electrochemical in situ Raman spectroscopic technique was established in author's lab and some research works have been done on it in the past two years. A brief review of these works is given in this paper. The electrochemical in situ Raman spectroscopic measurements were carried out using a Super LABRAM Raman spectrometer (Dilor, France) coupled with a CHI604A Electrochemical Analyzer (CH Instr., USA). A Teflon spectroelectrochemical cell with a quartz plate window was designed for the in situ measurements. The working electrode was pretreated with oxidation?reduction cycles for each measurement. The electrolyte solutions were purged with nitrogen prior to all measurements, and all the measurements were carried out under the nitrogen atmosphere. Copper, zinc superoxide dismutase (SOD) is an important oxidoreductase for organism metabolism. The established spectroelectrochemical technique was first used to characterize the cyclic voltammetric process of SOD at L?cysteine modified gold electrode as well as the process of electrochemical modification of L?cysteine molecules on a gold electrode. The obtained Raman spectra reveal that the L?cysteine modified gold electrode improves effectively the reversibility of electron?transfer reactions of SOD. Besides L?cysteine molecules, it was interesting that adenine was also an effective electron?transfer promoter for SOD at gold electrode. A strong peak at 355 cm -1 can be observed in the Raman spectrum of adenine molecules adsorbed on gold electrode. It was inferred that the peak maybe related to the chemical interaction between adenine molecules adsorbed and gold electrode surface. As shown in Fig.1, for the mixture of SOD and adenine at gold electrode under a polarization potential 55 mV (vs. SCE), both the characteristic Raman lines of SOD and adenine molecules appeared. Therefore it was reasonable to conclude that SOD and adenine molecules should be co?adsorbed on gold electrode surface under such a potential, which is slightly lower than the reduction peak potential of SOD on adenine?modified gold electrode. Moreover, two new peaks appeared remarkably at 445 cm -1 and 610 cm -1 are likely to be related to the active site of SOD. It suggests that the co?adsorption mechanism of SOD and adenine molecules on the gold electrode surface results in effective approaching of the active site of SOD to the electrode surface.作者联系地址：上海师范大学化学系!上海200234,上海师范大学化学系!上海200234,上海师范大学化学系!上海200234,上海师范大学化学系!上海200234,上海师范大学化学系!上海200234,上海师范大学化学系!上海200234Author's Address: Dept. of Chem., Shanghai Teachers Univ., Shanghai 200234,Chin

Application of ARM and linux in traffic flow detecting

针对交通流量检测系统的现状,提出了当前系统存在的问题以及可行的改善方法,进而以毫米波雷达作为交通流量信息的传感器设计了基于ARM的交通流量检测器。通过对交通雷达的工作原理和信号处理流程的分析,给出了交通流量检测系统的结构,对ARM控制单元各个模块的硬件电路进行了分析与设计,并移植了Linux操作系统。该设备可以实时的检测交通流量信息,易于扩展,安装维护方便,能够有效地改善现有系统

串联质谱代谢分析一种快速敏感的诊断胆石症的有效手段

为探讨氨基酸代谢异常与胆石症发病之间的关系,通过串联质谱分析法检测了128例胆石症患者和179例对照组样本的23种氨基酸、26个酰基肉碱及44个相对应的比值,并对这93个代谢指标进行了差异性分析研究.结果发现:与对照组相比,两组间有明显的代谢改变.胆石症组的C4-OH、Orn/Cit、C5/C2、C8/C10指标的代谢水平高于对照组;而Hcy、Ala、Cys、Met/Phe、Val/Phe指标代谢水平低于对照组.与此同时,构建了回归模型,发现上述异常氨基酸对胆石症预测的准确度为97.2%.这项研究证明了靶向代谢组学是快速诊断胆石症的有效手段

串联质谱代谢分析一种快速敏感的诊断胆石症的有效手段

为探讨氨基酸代谢异常与胆石症发病之间的关系,通过串联质谱分析法检测了128例胆石症患者和179例对照组样本的23种氨基酸、26个酰基肉碱及44个相对应的比值,并对这93个代谢指标进行了差异性分析研究.结果发现:与对照组相比,两组间有明显的代谢改变.胆石症组的C4-OH、Orn/Cit、C5/C2、C8/C10指标的代谢水平高于对照组;而Hcy、Ala、Cys、Met/Phe、Val/Phe指标代谢水平低于对照组.与此同时,构建了回归模型,发现上述异常氨基酸对胆石症预测的准确度为97.2%.这项研究证明了靶向代谢组学是快速诊断胆石症的有效手段

大功率GaInP／AlGaInP半导体激光器

制备了大功率实折射率GaInP／AlGaInP压应变分别限制量子阱激光器．所用外延材料在15°偏角的GaAs衬底上由有机金属气相外延一次外延生长得到．制备的激光器具有双沟脊波导结构，条宽和腔长分别为3和900μm，前后端面分别蒸镀5％的增透膜和95％的高反膜．分析了室温连续激射时激光器的光电输出性能．阈值电流的典型值为32mA，光学灾变阈值为88mW，功率为80mW时的工作电流为110mA，斜率效率为1W／A，串联电阻为3Ω．基横模光输出功率可达60mW，60mW时的平行结和垂直结的远场发散角分别为10°和32°，激射波长为658．4nm．器件的内损耗为4．1cm^-1，内量子效率达80％，透明电流密度为648A／cm^2

β-葡萄糖醛酸苷酶荧光底物试卤灵葡萄糖醛酸苷的高效制备

以猴肝微粒体（Cy LM）为酶源,采用生物制备法实现了荧光底物试卤灵（Resorufin）向试卤灵葡萄糖醛酸苷（Resorufinβ-D-glucuronide）的高效转化,同时借助新型色谱分离材料C18WAX及固相萃取技术实现了Resorufinβ-D-glucuronide的高效富集及选择性洗脱,最终获得纯度大于98%的目标产物.所得产物结构经LC-MS,1H NMR和13C NMR等手段进行了表征.在此基础上,以该葡萄糖醛酸产物为探针底物建立了β-葡萄糖醛酸苷酶活性检测及抑制剂高通量筛选的方法