Native Protein Separation by Isoelectric Focusing and Blue Gel Electrophoresis-Coupled Two-Dimensional Microfluidic Chip Electrophoresis

The use of microfluidic chip-based two-dimensional separation holds great promise in the proteomics field, given its portability, simplicity, speed, efficiency, and throughput. However, inclusion of sodium dodecyl sulfate, reported to be necessary for increasing protein-resolving capability, was also accompanied by the loss of both protein conformation and biological function. Here, we describe separation of native proteins by introducing blue native gel electrophoresis into isoelectric focusing and gel electrophoresis (IEF/CGE)-coupled protein two-dimensional microfluidic chip electrophoresis. After assessing the influence of various experimental conditions, the best separation ability and reproducibility of blue native IEF/CGE (IEF/BN-CGE) chip electrophoresis achieved until now were demonstrated no matter whether with a simple simulated mixture or with a complex mixture of total Escherichia coli proteins. Finally, instead of theoretical calculations, the image analysis technique was also used for the first time to quantitatively evaluate the actual peak capacities of chip electrophoresis. According to the number of features abstracted in the electrophoresis patterns, the superiority of the IEF/BN-CGE two-dimensional microfluidic chip electrophoresis was then exhibited quantitatively. The high native protein separation performance makes this established chip electrophoresis method possible for further application in widely needed drug screening, analysis of bio-molecular function, and assays of protein–protein interactions.     

Effect of TiMn1.5 alloying on the structure,hydrogen storage properties and electrochemical properties of LaNi3.8Co1.1Mn0.1 hydrogen storage alloys

A series of experiments were performed to investigate the effect of TiMn_1.5 alloying on the structure, hydrogen storage properties and electrochemical properties of LaNi_3.8Co_1.1Mn_0.1 hydrogen storage alloys at 303 K. For simple, A, B, and C are used to represent alloys (x = 0 wt %, x = 4 wt % and x = 8 wt %) respectively. The results of XRD and SEM show that LaNi_3.8Co_1.1Mn_0.1?xTiMn_1.5 hydrogen storage alloys have LaNi₅ phase and (NiCo)₃Ti phase. Based on the results of PCT curves, the hydrogen storage capacities of LaNi_3.8Co_1.1Mn_0.1?xTiMn_1.5 hydrogen storage alloys are about 1.28 wt % (A), 1.16 wt % (B) and 1.01 wt % (C) at 303 K. And the released pressure platform and the pressure hysteresis decrease with the increase of TiMn_1.5 content. Meanwhile the activation curves show that LaNi_3.8Co_1.1Mn_0.1?xTiMn_1.5 hydrogen storage alloy electrodes can be activated in three times and the maximum discharge capacity is 343.74 mA h/g at 303 K. In addition, with the increase of TiMn_1.5 content, the cyclic stability of the hydrogen storage alloy electrodes decreases obviously and the capacity retention decreases from 76.70% to 70.00% when TiMn_1.5 content increases from A to C. It also can be seen that LaNi_3.8Co_1.1Mn_0.1?xTiMn_1.5 hydrogen storage alloy electrode C and B have the best self-discharge ability and the best high-rate discharge ability from self-discharge curves and high-rate discharge curves.     

Homogeneous chemiluminescence system in neutral and near neutral aqueous solution with ClO2 as oxidant and its analytical application

Using ClO₂ as chemiluminescence (CL) oxidant, a novel homogeneous CL system in neutral and near neutral aqueous solution is proposed in this paper. ClO₂ could oxidize sulfite in pH 5.0–8.5 acetate buffer to produce CL emission, and pipemidic acid could sensitize the CL system. The ClO₂–SO₃²⁻–pipemidic acid reaction was used as a model CL system and explored the possibility of highly active and eco-friendly ClO₂ being used as CL oxidant in neutral and near neutral aqueous solution. Combined with flow-injection analysis, the proposed CL system was applied to the automated dissolution testing of pipemidic acid tablet. Compared with the common strong acidic or strong basic CL system, this proposed CL owns its advantages.     

Preparation, characterization and properties studies of quinine-imprinted polymer in the aqueous phase

The uniform-sized spherical molecularly imprinted polymers were successfully prepared through molecular imprinting technology by two-step seed swelling and mini-emulsion polymerization in the aqueous condition using quinine as template molecules and methacrylic acid (MAA) as functional monomer. The polymers were characterized by IR spectra, thermal-weight analysis, scanning electron microscope and laser particle size analysis. The properties of imprinted polymers were investigated in different organic phases and aqueous media. In the organic media, results suggested that polar interactions (hydrogen bonding, ionic interactions) between acidic monomer/polymer and template molecules are mainly responsible for the binding and recognition; whereas in the aqueous medium, a considerable recognition effect was also obtained where the ionic (electrostatic) interaction and hydrophobic interaction play an important role. The experiments of binding different substrates indicated that the MIPs possessed an excellent rebinding ability and inherent selectivity to quinine. __________ Translated from Zhongshan Dcocue Xuebao/Acta Scientianum Natralium University Sunyatseni, 2005, 44(3)(in Chinese)     

杂多酸催化合成乙酸乙酯

回流吸附法制备的负载型12-钨磷酸(HPW/C)是合成乙酸乙酯的高效催化剂。最佳反应条件下乙醇转化率达96％,酯化选择性100％。催化剂的高活性是由于HPW在活性炭上高度分散,使活性位增多,有效酸量增大。HPW/C还具有热稳定性高和不易流失等优点。     

催化极谱法测定L-谷氨酸的应用与研究

本文提出了催化极谱法测定L-谷氨酸的新体系并建立了相应的分析方法,对体系的反应机理也进行了初步研究。实验结果表明:当体系pH为8～10,[Cu~(2 )]=5×10~(-4)M,硼砂浓度为0.04M时,L-谷氨酸于-1.10V处产生一个清晰、灵敏的催化波。当其浓度为10~(-5)～10~(-6)M时,与峰高成良好的线性关系。机理实验结果证明,此波为吸附催化氢波。     

巴戟滋补膏对甲低阳虚兔肝和脑中五种微量元素的影响

采用电感耦合等离子体原子发射光谱法．对甲状腺切除兔(阳虚组)、甲状腺切除后微服巴戟滋补膏兔(中药组)以及对照组实验免肝和脑中锌、铜、铁、锰、铬5种元素进行检测．结果表明，甲低阳虚兔肝和脑中锌／铜值下降；灌服巴戟滋补膏使造型兔病情改善的同时可使其肝中元素改变好转．     

蒙特卡洛模拟退火与距离限制相结合的方法在多肽溶液构象分析中的应用

多维核磁共振技术的飞速发展议得其在生物大分子结构测定方面的应用已经达到可以与【射线晶体学并驾齐驱的地步．蛋白质结构堆积紧密，较适合于用核磁共振方法给出确定的结构．与蛋白质不同的是多肽的柔性较大，在溶液中可能存在多种构象，核磁共振实验给出的只是平均信息＊．利用核磁，（振数据构建分子结构模型常用的方法有距离几何、分子动力学等，在由核磁共振NOESZ得到的距离信息足够多时可以给出较好的结果问．由于多肽本身的特点：柔性较大，由核磁共振得到的距离信息较少等，利用距离几何、分子动力学方法进行构象搜索时容易陷入…     

乙二醇在电解银表面的氧化

用超高真空程序升温反应谱和瞬时应答方法研究了乙二醇在电解银表面的氧化，实验表明，室温下乙二醇吸附在电解银表面，并在３４３Ｋ分解给出一组产物群，预吸附氧与乙二醇反应时，在３４３Ｋ，４３３Ｋ和６１２Ｋ处给出三组产物群，它们分别对应于不同的表面反应，并给出了电解银催化乙二醇制乙二醛的活性结果。     

代铬刷镀层的耐腐蚀机理的考察

对新型的代铬刷镀层Ni-Fe-W-P-S进行了耐腐蚀性能机理的分析研究。用扫描电镜(SEM)、透射电镜(TEM)、扫描隧道显微镜(STM)、X射线衍射及电子能谱(XPS)等的分析表明，基体组织为非品结构是代铬刷镀层优异耐腐蚀性的主要原因.