锌掺杂碳量子点“关-开”型荧光探针检测果蔬中谷胱甘肽的研究

以柠檬酸、乙二胺和乙酸锌为前体,采用一步水热法制备了一种稳定的、高荧光量子产率的水溶性锌掺杂碳量子点(Zn-CQDs)。通过透射电子显微镜(TEM)、X射线衍射(XRD)、傅立叶红外光谱(FTIR)、紫外-可见吸收光谱(UV-Vis)、荧光光谱对Zn-CQDs的结构和光学性能进行了表征。研究表明,Cu~(2+)对Zn-CQDs的荧光产生猝灭,体系的荧光信号处于"关闭"状态,还原型谷胱甘肽(GSH)的存在,使Zn-CQDs-Cu~(2+)体系的荧光得以恢复,体系的荧光信号处于"打开"状态。由此构建了"关-开"型荧光探针用于谷胱甘肽(GSH)的选择性、高灵敏检测。探究了反应p H值和反应时间对荧光恢复体系的影响,同时考察了果蔬中常见的有机小分子和离子对Zn-CQDs-Cu~(2+)体系荧光强度的影响,在最佳实验条件下,GSH浓度在0. 05～80μmol/L内与Zn-CQDs荧光恢复率呈线性关系,检出限达63 nmol/L。将该探针用于果蔬中GSH的检测,样品的加标回收率为98. 6%～101%,相对标准偏差为1. 8%～3. 1%,结果令人满意。     

不同的引导肽对丝状噬菌体基因8蛋白展示外源多肽的影响

为了研究不同的引导肽对在基因8蛋白上展示外源多肽的影响,利用基因工程方法将一短肽插入基因8蛋白的N端,并将引导多肽去除或用基因3蛋白的引导肽序列替代基因8的引导肽序列.采用放射性脉冲追踪技术检测不同的引导肽对在基因8蛋白上展示外源多肽的作用.结果表明,无引导肽序列的引导,蛋白前体无法向成熟蛋白转化.基因3蛋白的引导肽可以引导展示有外源多肽的基因8蛋白,完成从前体向成熟蛋白的转化,但转化率明显下降.研究结果对阐明噬菌体外壳蛋白在大肠杆菌中的跨膜机制具有重要的意义.     

二芳基取代-1,2,4-三唑类化合物的合成及其抗炎活性研究

以选择性环氧化酶-2(COX-2)抑制剂Celecoxib为先导,根据其构效关系和分子模拟研究结果,应用生物电子等排原理等药物设计方法,设计合成了19个结构全新的二芳基取代-1,2,4-三唑类衍生物,其结构经IR,¹HNMR,MS和元素分析确证.初步的药理试验结果表明,部分目标化合物具有一定的抗炎活性.     

S~2O~8^2^-处理的ZrO~2固体超强酸上的正丁烷异构化反应

首次报道了由浸渍过硫酸根的方式制备固体超强酸.讨论了焙烧温度、浸渍浓度以及ZrO_2前驱体沉淀条件对样品性质的影响,并研究了它们对正丁烷异构化反应性能.实验结果表明,600～650℃焙烧、0.25～0.50mol/LS_2O_8~(2-)浸渍反加沉淀的ZrO_2具有最高超强酸性.与相同条件下制备的SO_4~(2-)/ZrO_2相比,S_2O_8~(2-)/ZrO_2上正丁烷250℃异构化活性是SO_4~(2-)/ZrO_2的2倍,可能是由于它具有较多的中强酸位并具有与SO_4~(2-)/ZrO_2不同的活性位结构.     

金纳米花的合成及其与人血清白蛋白相互作用的研究

采用晶种法合成了金纳米花（AuNFs）。利用紫外可见吸收光谱法和原子力显微镜方法对金纳米花进行了表征,结果表明制备的金纳米花呈蓝紫色,在549nm处有特征吸收峰,且形状为花状。借助紫外可见吸收光谱法和荧光光谱法研究了AuNFs与人血清白蛋白（HSA）的结合过程。当AuNFs与HSA相互作用时,随着AuNFs溶液浓度的增加,HSA的紫外吸收峰强度也随之增加,但荧光光谱强度则发生了猝灭。由变温荧光实验可以获得两者相互作用的热力学参数,如结合常数（K_a）、吉布斯自由能变（ΔG）、熵变（ΔS）、焓变（ΔH）。ΔG<0表明在溶液中AuNFs与HSA可以自发结合发生反应并形成复合物;ΔH<0、ΔS<0表明结合过程以范德华力和氢键为主。同步荧光和3D荧光实验均表明,AuNFs的存在使得HSA的构象以及周围的环境发生了改变。     

Metabolomics study of the effect of Danggui Buxue Tang on rats with chronic fatigue syndrome

Danggui Buxue Tang (DBT), a traditional Chinese medicine (TCM) formula for ‘invigorating qi and enriching blood’, has been reported to produce a good effect on chronic fatigue syndrome (CFS). However, the related mechanism remains largely undetermined. This study devised a metabolomics approach with GC–MS combined with pattern recognition to estimate the extent to which DBT alleviated CFS induced by food restriction and force swimming in rats. After 4 weeks of treatment, the endurance capability of rats was significantly better, and the motionless time was significantly shorter in the DBT group than in the CFS model group. Moreover, the activities of superoxide dismutase and glutathione peroxidase increased, whereas the levels of malondialdehyde, interleukin 6, and tumor necrosis factor alpha decreased in the DBT treatment group. Fifteen significantly changed metabolites were observed in the serum of rats with CFS, which was reversed markedly by DBT treatment. Metabolic pathway analysis showed that DBT could possibly alleviate CFS in rats by regulating the biosynthesis of phenylalanine, tyrosine, and tryptophan and the metabolism of glycine, serine, threonine, glycerolipid, glyoxylate, dicarboxylate, and tyrosine. It was observed that the metabolism of glycine, serine, and threonine was most closely related to the improvement in CFS by DBT treatment. This study showed that DBT could improve CFS effectively, and metabolomics was a powerful means to gain insights into the TCM formulas against CFS.     

Direct Synthesis of An Aluminosilicate POS Zeolite with Intersecting 12×11×11-Member-Ring Pore Channels by Using a Designed Organic Structure-Directing Agent

Large and extra-large pore zeolites have been widely applied in industrial areas as catalysts, adsorbents, etc. Among them, silica and/or aluminosilicate zeolites have been attracted great attention due to their excellent hydrothermal stability and strong acidity. However, a great deal of zeolite structures are still not available in the form of silica and/or aluminosilicate. Herein, we report the synthesis of pure silica and aluminosilicate large-pore zeolites, denoted as NUD-14 and Al-NUD-14, respectively, by using a designed cation 1-ethyl-4-phenylpyridinium as an organic structure-directing agent (OSDA). NUD-14 has an intersecting 12×11×11-member ring pore system, which is isostructural to the germanosilicate PUK-16 zeolite with a POS topology. The OSDAs can be completely removed from the framework by calcination. NUD-14 and Al-NUD-14 possess excellent acid and hydrothermal stabilities, superior to the germanosilicate POS zeolite. The incorporation of Al into the zeolite framework makes the Al-NUD-14 zeolite possess medium and strong acidities. The successful synthesis of NUD-14 consisting of a rare odd-member ring pore structure may provide a platform for interesting size- and shape-selective catalytic applications.     

铜粒子负载泡沫基相变复合材料的制备与性能

以三聚氰胺泡沫(MF)经高温碳化后制得的碳泡沫(CF)为基体, 以氯化铜(CuCl₂)和水合肼(N₂H₄·H₂O)溶液为前驱体, 利用氧化还原反应在泡沫骨架上生成铜粒子, 然后通过真空浸渍法将聚乙二醇(PEG)封装在基体中制得相变复合材料. 利用扫描电子显微镜(SEM)、 X射线衍射仪(XRD)、 差示扫描量热仪(DSC)和红外热成像仪等研究了相变复合材料的形貌、 结构和热性能. 结果表明, 当CuCl₂浓度为1.0 mol/L时, Cu粒子均匀致密地沉积在CF骨架表面, 制得的相变复合材料在具备良好密封性能的前提下, 相变潜热可高达145.2 J/g, 热效率超过80%, 光热转换效率达到83.8%, 且呈现出优异的储热能力和调温性能. 本文为制备综合性能优异的相变复合材料提供了一种策略, 有利于拓宽相变复合材料的应用领域.     

A capillary electrophoresis method for the determination of soluble monosaccharides in Ginkgo biloba leaves

A method for the simultaneous determination of six monosaccharides by pre-column derivatization with 1-phenyl-3-methyl-5-pyrazolone and capillary electrophoresis was developed in this work. The derivatization (i.e., reaction temperature, capillary electrophoresis duration, and extraction number) and separation (i.e., pH and buffer concentration) conditions for capillary electrophoresis were optimized. Results showed that the limits of detection under optimal conditions were in the range of 0.036–0.35 mg/L with a mean correlation coefficient >0.99. The recoveries were in the range of 87.3–108.49%, and the relative standard deviations of intra- and inter-day variations were in the ranges of 2.2–3.8 and 3.2–5.0%, respectively. The method was successfully applied to the analysis of six free monosaccharides in three types of Ginkgo biloba leaves.     

两个Gd2配合物的晶体结构及磁制冷性质

使用多齿席夫碱配体（H₂L=pyridine-2-carboxylic acid （3,5-di-tert-butyl-2-hydroxy-benzylidene）-hydrazide）分别与Gd （dbm）₃·2H₂O （Hdbm=二苯甲酰基甲烷）及Gd （NO）₃·6H₂O反应,通过溶剂热法得到了2个新的Gd₂配合物[Gd₂（L）₂（dbm）₂（C₂H₅OH）₂]（1）和[Gd₂（L）₂（HL）₂（DMF）]·2CH₃CN （2）（DMF=N,N-二甲基甲酰胺）,并对其结构与磁性质进行了系统的研究。单晶结构分析表明配合物1中的每个中心Gd(Ⅲ)离子均为8配位,其配位几何构型为略微变形的三角十二面体,相邻的中心Gd(Ⅲ)离子通过2个μ₂-O连接形成了平行四边形的Gd₂O₂核心;配合物2中的每个中心Gd(Ⅲ)离子均为9配位,其配位几何构型为扭曲的球形单帽四方反棱柱,相邻的中心Gd(Ⅲ)离子通过3个μ₂-O连接形成了三角双锥形的Gd₂O₃核心。磁性测试表明配合物1和2具有磁制冷性质,其最大磁熵变（-ΔS_m）分别为20.16 J·K^-1·kg^-1（T=2.0 K,ΔH=70 kOe）和17.14 J·K^-1·kg^-1（T=2.0 K,ΔH=70 kOe）。