Morphine-induced conditioned place preference in mice: Metabolomic profiling of brain tissue to find “molecular switch” of drug abuse by gas chromatography/mass spectrometry

Conditioned place preference (CPP) is a widely used model to explore the mechanism of context-dependent learning. In this work, we developed a GC–MS method to investigate the metabolites in mice brain which was used to study the mechanism of context-dependent learning associated with rewarding effect of morphine. Metabolites were extracted from brain tissues and derivatized followed by analysis by gas chromatography/mass spectrometry (GC–MS). In total, 69 peaks were identified as known compounds. By a Wilcoxon ran sum test with p value ≤0.05, 21 metabolites were selected and considered as the potential biomarkers of morphine in mice brain. Using principal component analysis (PCA) and receiver-operator characteristic (ROC) curves, a model was constructed with a combination of these 21 metabolic markers. Multivariate statistics of the model yielded separation between the two groups with an area under the curve value of 0.947. Some metabolites were further discussed in detail about their pathway. Results showed that our technique can be successfully applied to profile for biomarkers and in understanding molecular mechanisms of drug abuse.     

Synthesis, photophysical and electrochemical properties and theoretical studies on three novel indolo[3,2-b]carbazole derivatives containing benzothiazole units

Three novel indolo[3,2-b]carbazoles derivatives were successfully synthesized by condensation reaction and structurally characterized by elemental analysis, mass spectrometry and proton nuclear magnetic resonance spectroscopy methods, which belong to donor-π-acceptor systems comprising an indolo[3,2-b]carbazole group as an electron donor and two benzothiazole rings as electron acceptors. The thermal, electrochemical and photophysical properties of the compounds were characterized by thermogravimetric analysis combined with electrochemistry, UV-vis absorption spectroscopy and fluorescence spectroscopy. On the other hand, the geometries, molecular orbitals, charge-injection and transport properties were determined by quantum chemical calculations. The results show that the compounds synthesized exhibit good thermal stability and high fluorescence quantum yields, indicating the potential application as optoelectronic materials.     

15种中成药中有害重金属铅、镉、铜含量的测定

为了解中药重金属污染情况,测定了市售常用15种中成药中重金属铅、镉、铜的含量,其中铅、镉采用石墨炉原子吸收法,铜采用火焰原子吸收法测定.结果表明,15种中成药均不同程度被这3种重金属污染,通心络中铅、镉、铜含量都已超标,桑菊感冒片镉超标,中药重金属污染问题仍然存在.     

LiTFSI/2-噁唑烷酮电解液与不同微结构碳材料的电化学兼容性

二（三氟甲基磺酸酰）亚胺锂（LiTFSI）与1,3-氮氧杂环戊-2-酮（OZO）形成的离子液体具有良好的物理和电化学性能,表现出宽的液相温度范围和高的离子电导率,可满足超级电容器的应用需求。本文制备的LiTFSI-OZO离子液体体系中,各种离子的结构组成（如自由离子、离子对、积聚离子）及其之间的相互作用对离子液体的电化学性能具有较大的影响,将其作为电解液应用于不同微结构特性（孔径、比表面积等）的炭材料（碳纳米管(CNTs)、中孔活性炭(MEACs)和微孔活性炭(MIACs)）作为电极的电化学双层电容器中,电化学兼容性研究表明,由于中孔活性炭电极材料有最大的比表面积及最适宜的孔径分布,相应的模拟电容具有最高的比容量184.6 F?g-1。该研究表明,对电极材料的微结构特性与离子液体离子尺度进行优化匹配是实现离子液体作为电解液应用于超级电容器的关键。     

微波合成Pt/WC催化剂及其对甲醇的电催化性能

分别采用微波加热乙二醇还原法(MW)和浸渍还原法(IR)制备以碳化钨(WC)为载体的Pt/WC催化剂, 并分别标记为: MW-Pt/WC及IR-Pt/WC. 用XRD、SEM对两种方法制备的复合材料的结构与形貌进行表征. 循环伏安测试结果表明MW-Pt/WC催化剂在酸性条件下的甲醇氧化性能比IR-Pt/WC催化剂更优, 表现在同一电位下MW-Pt/WC催化剂具有更高的电流且其氧化起始电位负移约30 mV, 还具有更大的电化学比表面积. 此外计时电流法实验结果表明MW-Pt/WC催化剂的稳定性高于IR-Pt/WC催化剂.     

Simultaneous determination of cadmium(II), lead(II) and copper(II) by using a screen-printed electrode modified with mercury nano-droplets

We are presenting a strategy for the fabrication of disposable screen-printed electrodes modified with mercury nano-droplets and capable of sensing heavy metal ions. They were prepared by coating electrodes with a mixture of multi-walled carbon nanotubes and chitosan, this followed by adsorption of mercury. The resulting sensor was characterized by cyclic voltammetry and impedance spectroscopy. Also the effects caused by adsorption of mercury were investigated. It is shown that square wave anodic stripping voltammetry enables simultaneous determination of cadmium(II), lead(II) and copper(II), for which detection limits of 12, 23 and 20 nM, respectively, are found. Relative standard deviations for ten determinations at 0.6 µM concentrations of these ions are in the range of 3.0 to 5.7%. The applicability was tested by analyzing river water and showed recoveries between 94.1 and 104.6%, thus demonstrating its utility for in-field monitoring of these heavy metal ions.     

Synthesis and biological evaluation of novel benzothiazole-2-thiol derivatives as potential anticancer agents

A series of novel benzothiazole-2-thiol derivatives were synthesized and their structures determined by 1H-NMR, 13C-NMR and HRMS (ESI). The effects of all compounds on a panel of different types of human cancer cell lines were investigated. Among them, pyridinyl-2-amine linked benzothiazole-2-thiol compounds 7d, 7e, 7f and 7i exhibited potent and broad-spectrum inhibitory activities. Compound 7e displayed the most potent anticancer activity on SKRB-3 (IC(50) = 1.2 nM), SW620 (IC(50) = 4.3 nM), A549 (IC(50) = 44 nM) and HepG2 (IC(50) = 48 nM) and was found to induce apoptosis in HepG2 cancer cells.     

烯唑醇免疫亲和色谱柱的制备及其在样品前处理中的应用

将四甲氧基硅烷(TMOS)水解后与烯唑醇抗体聚合,采用溶胶-凝胶法合成了烯唑醇免疫亲和色谱(IAC)柱固定相,并用其制备了对烯唑醇具有特异性亲和力的IAC柱。对IAC柱条件进行了优化,选择超纯水作为吸附与平衡介质,30%～50%(体积分数)甲醇水溶液作为洗脱剂。结果表明: 在优化条件下,IAC柱对烯唑醇的动态柱容量达125.4 μg/g。在河水样品和水果样品中添加烯唑醇,经IAC柱净化富集,洗脱液采用高效液相色谱检测,河水中烯唑醇的平均回收率为90.36%～100.14%,相对标准偏差(RSD)为2.03%～6.08%;水果中烯唑醇的平均回收率为85.55%～94.02%, RSD为3.38%～6.78%。本研究为烯唑醇在河水、水果等样品中的残留分析提供了一种新的高效前处理手段。     

HPLC-MS/MS enantioseparation of triazole fungicides using polysaccharide-based stationary phases

The enantiomeric separation of 21 triazole fungicides was carried out on four polysaccharide-derived chiral stationary phases in the reversed phase separation mode using high performance liquid chromatography coupled with tandem mass spectrometry. All fungicides were detected in electrospray ionization (ESI) positive mode with selected reaction monitoring (SRM). Complete enantioseparation was achieved for 21 fungicides except for difenoconazole based on cellulose tris (3,5-dimethylphenylcarbamate) and cellulose tris (3-chloro-4-methylphenyl carbamate) columns by optimizing experimental conditions including mobile phase and column temperature. Mobile phase was 0.1% formic acid aqueous solution mixed with methanol or acetonitrile in different proportions. Among all the fungicides, 15 with two enantiomers and three with four stereoisomers (bitertanol, bromuconazole, and cyproconazole) were successfully separated at 25°C. Enantioseparation for the other three fungicides (propiconazole, triadimenol, and difenoconazole) with four stereoisomers could be achieved by changing the column temperature from 10 to 40°C. Propiconazole and triadimenol were enantioseparated on baseline at 40 and at 35°C, respectively, and difenoconazole was enantioseparated partially with the R(s) > 1.1 at 25°C. Moreover, linearities and limits of detection (LODs) of 21 fungicides except for difenoconazole were studied, showing coefficients of determination (R(2)) higher than 0.99 and LODs lower than 2.5 μg/L.