聚甲基丙烯酸甲酯微流控芯片分离DNA片段的初步研究

自从1995年Mathies^[1]首次将微流控芯片毛细管凝胶电泳用于基因测序研究以来,DNA片段的分离已成为微流控芯片应用的重要领域之一.最早应用于DNA分析的微流控芯片是玻璃芯片,聚合物微流控芯片以其品种多、成本低、易于加工,与玻璃芯片相比具有封接温度大大降低,微通道内电渗流显著减小等特点,已被成功应用于DNA片段的分离^[2,3].     

基于BioMEMS技术的DNA固相萃取芯片的制备

基于BioMEMS技术,制备一种新型的Si-PDMS-玻璃结构的DNA固相萃取微流控芯片。在硅基片上制备4种固相载体,分析不同载体的性质和制备特点,优选多孔氧化硅作为萃取DNA的固相载体。对比研究芯片的封装工艺,优选压制法制备PDMS-玻璃盖片,采用粘接技术封装芯片。芯片成功提取老鼠全血中的基因组DNA,提取效率为23.5×10-9g/μL全血,并成功进行PCR反应,达到试剂盒水平。固相萃取微流控芯片具有与其他样品处理芯片、PCR芯片和电泳芯片相集成的潜力,可实现对复杂生物样品的检测和分析。     

一种新型双吖啶核酸探针的合成及应用

首次成功地合成了一种新型的双吖啶DNA荧光探针,其结构经^1H NMR,IR及元素分析确证。用光谱法研究了该探针与DNA的作用方式,发现两者之间存在嵌插作用。     

用于提取外周血DNA微流控样品预处理芯片的研制

基于固相萃取原理和微电子机械系统(Micro-Electro-Mechanical System, MEMS)技术研制了一种多孔氧化硅微流控样品预处理芯片, 并利用具有大比表面积的多孔氧化硅作为提取DNA的固相载体, 从而大大提高了DNA的提取产率. 分析了影响DNA提取产率的因素, 改进了芯片制备工艺和DNA提取实验方案, 成功地提取了小鼠外周血DNA, 提取产率为24 ng/(μL全血), 达到商用试剂盒水平. 同时以该DNA作为PCR扩增模板, 扩增效果良好.     

含钛玻璃光学碱度的测量

以Ｃu＾２＋为探针，成功地测得了含钛玻璃体系的光学碱度，并发现二氧化钛对体系组合 碱度的贡献与基质玻璃度有关，而且并非总是同一常数，这一结果将有助于进一步解决这类体系的碱度测量问题。     

交联SE-54弹性玻璃毛细管柱研究

弹性玻璃毛细管柱的出现为毛细管色谱技术提供了一种新型柱。最近我们应用硅膜改性法成功地惰化了弹性玻璃毛细管柱而不损害其强度,使这种柱型有了良好的发展基础。关于交联弹性石英柱的制备巳有不少研究,但在硅膜改性玻璃毛细管柱上进行交联的工作尚未见报道。本文介绍SE-54弹性玻璃毛细管交联柱的制备和性能研究。在拉制好的     

超微粒分子筛多孔层毛细管气相色谱柱的初步研制

探讨了以超微粒分子筛成功地沉积于玻璃毛细管内壁制备出新型ＰＬＯＴ柱的方法。实验证明,这种ＰＬＯＴ柱具有快速、高效、稳定和选择分离等独到特性。     

基于新型DNA金属化工艺银纳米线的制备

随着DNA金属化工艺逐渐发展, 以DNA为模板进行金属纳米线的制备, 使得生物与微细加工技术的结合变得可能. 我们将DNA模板金属化工艺加以改进, 利用半导体材料——硅作为样品衬底, 并在硅片上利用Parafilm疏水膜斜向拉伸排列DNA分子, 采用化学还原反应, 成功地进行了银纳米线的制备. 改进后的金属化工艺对DNA分子金属化程度较好, 而且制备出了金属纳米网状结构. 基于DNA构筑复杂纳米图形的实现, 进行相关的金属化, 有望构筑纳米集成电路.     

基于新型DNA金属化工艺银纳米线的备

随着DNA金属化工艺逐渐发展,以DNA为模板进行金属纳米线的制备,使得生物与微细加工技术的结合变得可能．我们将DNA模板金属化工艺加以改进,利用半导体材料——硅作为样品衬底,并在硅片上利用Parafilm疏水膜斜向拉伸排列DNA分子,采用化学还原反应,成功地进行了银纳米线的制备．改进后的金属化工艺对DNA分子金属化程度较好,而且制备出了金属纳米网状结构．基于DNA构筑复杂纳米图形的实现,进行相关的金属化,有望构筑纳米集成电路．     

碘化亚铜微晶掺杂硅酸盐玻璃的制备及其光学性质

采用可分相的Na2O－Al2O3－B2O3－SiO2系为基础玻璃，以CuO／SnO、NaI为原料分别引入Cu＋、I－，成功地制备出CuI激晶掺杂硅酸盐玻璃．通过X射线粉末衍射（XRD）和高分辨透射电镜（HRTEM）分析观察到玻璃中的晶相和微晶的分布情况；由玻璃的室温透射光谱研究了玻璃的热处理条件与光吸收性的关系．实验发现，该玻璃对Nd：YAG激光器腔内自由振荡具有脉定压缩效应．     

PMDA-BPDA-HAB聚苯并噁唑的合成及耐热性

PMDA-BPDA-HAB聚苯并噁唑的合成及耐热性;均苯四甲酸二酐;联苯四羧酸二酐;二羟基联苯胺;聚酰亚胺;聚苯并噁唑;耐热性     

Synthesis of Some Novel Class of Bis(isoxazoline) and Bis(aziridine) Derivatives

Synthesis of some new bis(isoxazoline) derivatives has been described from terepthaldehyde derived bis(nitrones) using microwave irradiation via 1,3‐dipolar cycloaddition reaction. Bis(isoxazoline) derivatives in turn successfully converted into new bis(aziridine) derivatives via Baldwin rearrangement. Simple reaction methodology, non involvement of catalysts, and good to excellent yields are the important features noticed in this synthesis.     

柴油加氢精制催化剂制备技术

柴油加氢精制催化剂制备技术的发展大致经历了3个阶段,由此形成了三代柴油加氢催化剂:单层分散的负载型金属硫化物催化剂,多层分散的负载型金属硫化物催化剂和非负载型金属硫化物催化剂。本文对金属硫化钼基柴油加氢精制催化剂的应用背景、制备思想及催化剂研究开发现状进行了系统的总结,对柴油加氢催化剂的发展方向进行了展望。     

Magnetism of metal-nitroxide compounds involving bis-chelating imidazole and benzimidazole substituted nitronyl nitroxide free radicals

Coordination compounds based on imidazole and benzimidazole substituted nitronyl nitroxide radicals with transition metal ions and trivalent lanthanide ions are described from the perspective of their magnetic properties.For the transition metal compounds the crystal structures show various metal-nitroxide dimensionalities including mononuclear (0D), one-dimensional (1D) and two-dimensional (2D) complexes. The mononuclear complexes were isolated with most metal ions of the first transition series. One copper(II) complex shows a copper(II)-radical ferromagnetic coupling (J = +75 cm⁻¹) while for the other mononuclear compounds, mainly with manganese(II), the metal-radical interactions are antiferromagnetic. The one-dimensional and two-dimensional complexes are manganese(II) compounds which show canting effects leading to weak ferromagnetism.For the trivalent lanthanide ions [La(III), Gd(III) and Eu(III)], three series of mononuclear complexes were obtained in which the metal center is bound to four, two or one nitroxide radicals depending on the counter ions and ancillary ligands. Unexpectedly, in most gadolinium(III) complexes, the Gd(III)-radical interactions were found to be antiferromagnetic in contradiction with other foundings and previous theoretical models. In support to the magnetic studies, the optical properties of the lantanide complexes have also been investigated and are briefly described.     

Transition metal complexes of the tripodal ligand 4-(2′-pyridylmethyl)-4-azaheptane-1,7-diamine. Crystal structures of [CuLCl]ClO4 and [NiL(MeCN)2](ClO4)2

The tripodal ligand 4-(2′-pyridylmthyl)-4-azaheptane-1,7-diamine has been prepared by reaction of 2-aminemethyl pyridine with acrylonitrile, followed by the reduction of the nitrile groups. Copper(II), nickel(II), zinc(II), cobalt(III) and chromium(III) complexes of the ligand have been prepared and characterized and the crystal structures of the complexes [CuLCl]ClO₄ and [NiL(MeCN)₂](ClO₄)₂ determined. The copper complex is five coordinate with approximate square pyramidal stereochemistry with the apical position occupied by a primary amine donor. The nickel complex is octahedral with the pyridine nitrogen donor lying trans to an acetonitrile ligand.     

Simple,Selective, and Sensitive Spectrophotometric Method for Determination of Trace Amounts of Nickel（Ⅱ）, Copper （Ⅱ）, Cobalt （Ⅱ）, and Iron （Ⅲ） with a Novel Reagent 2-Pyridine Carboxaldehyde Isonicotinyl Hydrazone

A selective and sensitive reagent of 2-pyridine carboxaldehyde isonicotinyl hydrazone（2-PYAINH） was synthesized and studied for the spectrophotometric determination of nickel, copper, cobalt, and iron in detail. At a pH value of 7.0, 9,0, 9.0, and 8.0, respectively, which greatly increased the selectivity; nickel, copper, cobalt, and iron reacted with 2-PYAINH to form a 1：2 yellow-orange, 1：2 yellow-green, 1：2 yellow and 1：1 yellow complexes, with absorption peaks at 363, 352, 346, and 359 nm, respectively. Under the optimal conditions, Beer＇s law was obeyed over the ranges of 0.01-1.4, 0.01-1.5, 0.01-2.7, and 0.01-5.4 mg/L respectively. The apparent molar absorptivity and Sandell＇s sensitivities were 8.4×10^4, 5.2×10^4, 7.1×10^4, and 3.9×10^4 L·mol^-l·cm^-1, respectively, and 0.00069, 0.0012, 0.00078, and 0.0014 μg·cm2, respectively. The detection limits were found to be 0.001, 0.002, 0.003, and 0.01 mg/L, respectively. The detailed study of various interfering ions to make the method more sensitive was carried out and selective and several real samples were analyzed with satisfactory results.     

Sample preparation and current applications of liquid chromatography for the determination of non-structural carbohydrates in plants

This article summarizes the current methods of determination of non-structural carbohydrates (NSCs) in plant samples based on liquid chromatography (LC). NSCs comprise several types of carbohydrates: sugar alcohols (e.g., sorbitol), monosaccharides (e.g., glucose and fructose), disaccharides (e.g., sucrose), oligosaccharides (e.g., raffinose) and polysaccharides [e.g., starch and polyfructans (e.g., inulin)]. NSCs are important in plant metabolism and have to be strictly distinguished from all sorts of structural carbohydrates (e.g., polysaccharide cellulose) that make up the backbone of the plants. Consequently, preservation of structural carbohydrates is a crucial step during sample preparation for NSC determination and is therefore addressed.Sugar alcohols, monosaccharides, disaccharides and those oligosaccharides that are easily soluble in polar solvents can be analyzed directly by high-performance LC. They are also referred to as free carbohydrates (FCs).However, polysaccharides are generally submitted to hydrolyzation into monomers prior to their quantitative analysis. This can be done either chemically, using acids, or enzymatically - both methods are discussed. For identification and quantification of the NSCs after LC separation, the following detectors are used: pulsed amperometry, refractive index, evaporate light scattering and finally, mass spectrometry.     

The development and application of guidance on equipment qualification of analytical instruments

 This paper describes the development of guidance for the equipment qualification (EQ) of analytical instruments. EQ is a formal process that provides documented evidence that an instrument is fit for its intended purpose and kept in a state of maintenance and calibration consistent with its use.     

Electrochemically selective determination of dopamine in the presence of ascorbic and uric acids on the surface of the modified Nafion/single wall carbon nanotube/poly(3-methylthiophene) glassy carbon electrodes

A voltammetric method based on a combination of incorporated Nafion, single-walled carbon nanotubes and poly(3-methylthiophene) film-modified glassy carbon electrode (NF/SWCNT/PMT/GCE) has been successfully developed for selective determination of dopamine (DA) in the ternary mixture of dopamine, ascorbic acid (AA) and uric acid (UA) in 0.1M phosphate buffer solution (PBS) pH 4. It was shown that to detect DA from binary DA-AA mixture, the use of NF/PMT/GCE was sufficient, but to detect DA from ternary DA-AA-UA mixture NF/SWCNT/PMT/GCE was required. The later modified electrode exhibits superior electrocatalytic activity towards AA, DA and UA thanks to synergic effect of NF/SWCNT (combining unique properties of SWCNT such as high specific surface area, electrocatalytic and adsorptive properties, with the cation selectivity of NF). On the surface of NF/SWCNT/PMT/GCE AA, DA, UA were oxidized respectively at distinguishable potentials of 0.15, 0.37 and 0.53 V (vs. Ag/AgCl), to form well-defined and sharp peaks, making possible simultaneous determination of each compound. Also, it has several advantages, such as simple preparation method, high sensitivity, low detection limit and excellent reproducibility. Thus, the proposed NF/SWCNT/PMT/GCE could be advantageously employed for the determination of DA in real pharmaceutical formulations.     

Simultaneous determination of mercury and arsenic by anodic stripping voltammetry

An electrochemical method for the simultaneous determinations of Hg^II concentration and total As^III and As^V concentration has been developed. The method does not require the additional preliminary step of the chemical reduction of As^V to As^III, or oxidation of As^III to As^V before stripping analysis takes place. Also, the method for the simultaneous determination of Hg^II concentration and As^III concentration is described. Measurements were performed in 0.1 M HCl using a gold-plated graphite electrode as sensor. Detection limits for both methods are below 0.4 ppb. Relative standard deviation did not exceed 15%. The possible interference by other trace metals was investigated. Analyses of natural water and industrial solutions were made using proposed methods and AAS. The t-test demonstrates that there was no significant difference between the results obtained with these methods. Proposed methods decrease the time of analysis because concentrations of the Hg^II and arsenic ions were measured simultaneously. Also, the removal of the additional step of chemical reduction of As^V to As^III or oxidation of As^III to As^V decreases analysis time, and also reduces the chance of contamination due to the use of additional reagents.