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111.
Shu-Ping Hui Toshihiro Sakurai Seiji Takeda Shigeki Jin Hirotoshi Fuda Takao Kurosawa Hitoshi Chiba 《Analytical and bioanalytical chemistry》2013,405(14):4981-4987
Herein, we represent a simple method for the detection and characterization of molecular species of triacylglycerol monohydroperoxides (TGOOH) in biological samples by use of reversed-phase liquid chromatography with a LTQ Orbitrap XL mass spectrometer (LC/LTQ Orbitrap) via an electrospray ionization source. Data were acquired using high-resolution, high-mass accuracy in Fourier-transform mode. Platform performance, related to the identification of TGOOH in human lipoproteins and plasma, was estimated using extracted ion chromatograms with mass tolerance windows of 5 ppm. Native low-density lipoproteins (nLDL) and native high-density lipoproteins (nHDL) from a healthy donor were oxidized by CuSO4 to generate oxidized LDL (oxLDL) and oxidized HDL (oxHDL). No TGOOH molecular species were detected in the nLDL and nHDL, whereas 11 species of TGOOH molecules were detected in the oxLDL and oxHDL. In positive-ion mode, TGOOH was found as [M + NH4]+. In negative-ion mode, TGOOH was observed as [M + CH3COO]–. TGOOH was more easily ionized in positive-ion mode than in negative-ion mode. The LC/LTQ Orbitrap method was applied to human plasma and three molecular species of TGOOH were detected. The limit of detection is 0.1 pmol (S/N?=?10:1) for each synthesized TGOOH. Figure
Analysis of triacylglycerol hydroperoxides in human lipoproteins by Orbitrap mass spectrometer 相似文献
112.
GUO Le ZHANG Xu-nong WANG Yu-Xiao WANG Shu-Ping YANG Shu-Tao 《结构化学》2009,28(8):1023-1027
The title compound {[Zn(NIT4Py)(fum)(HEO)2]·H2O}n, where NIT4Py = 2-(4'- pyridinyl)-4,4,5,5-tetra-methylimidazoline-looxyl-3-oxide and fum = fumarate, has been prepared and structurally characterized by X-ray diffraction. It crystallizes in triclinic, space group P1^- with a = 6.9533(9), b = 9.805(1), c = 15.248(2) A, α= 94.608(2), β = 92.328(2), γ = 105.840(2)°, C16H24N3O9Zn, Mr = 467.75, V = 994.8(2) A^3, Z = 2, Dc = 1.562 g/cm^3,μ(MoKα) = 1.289 mm^-1, F(000) = 486, the final R = 0.0243 and wR = 0.0622 for 3505 independent reflections with Rint = 0.0125. The Zn(II) adopts a distorted five-coordinate triangle bipyramidal geometry. The basic framework structure of the complex is a 1-D chain. The intrachain hydrogen bonds are helpful to stabilize the 1-D chain structure. Furthermore, the chains are connected by O-H…O hydrogen bonds to give a 2-D double-layer network. 相似文献
113.
联用色谱及多组分光谱相关色谱用于当归补血汤与单味药成分的比较研究 总被引:9,自引:0,他引:9
摘要利用HPLC-DAD提供的二维化学数据信息, 通过多组分光谱相关色谱方法及化学计量学分辨技术, 对相同试验条件下所得的当归补血汤及其单味药的色谱组分进行了比较和归属分析. 结果表明, 在当归补血汤色谱响应值较高的21个色谱峰中, 8个色谱峰的组分来自当归, 6个色谱峰的组分来自黄芪, 7个色谱峰的组分同时来源于当归和黄芪. 其中一些色谱峰簇中的其它组分发生了消长变化, 既有新物质的产生, 又有原有化学成分的消失, 说明中药复方配伍的药效物质基础不仅是各单味药化学成分的总和, 还有单味药在复方配伍过程中各种成分的相互作用. 本方法为中药复方与单味药化学组分的比较及归属分析, 尤其对重叠色谱峰簇的组分比较分析提供了方便、 快捷及可行的研究方法. 相似文献
114.
Hong-Zhen Xie Shi-Jie Huang Jin Zhou Shu-Ping Yu Dan-Yi Wei 《Transition Metal Chemistry》2010,35(7):773-778
Two coordination complexes, namely [Co(phen)(H2O)L]·H2O and [Ni2(phen)2(H2O)2L2]·4H2O (phen = 1,10-phenanthroline, H2L = 1,3-adamantanedicarboxylic acid) have been hydrothermally synthesized and structurally characterized by single crystal
X-ray diffraction. [Co(phen)(H2O)L]·H2O consists of 1D chains of the complex plus lattice H2O molecules. Interchain hydrogen bonds and π–π stacking interactions assemble the 1D chains into 2D layers. [Ni2(phen)2(H2O)2L2]·4H2O is a binuclear complex which is assembled into a 3D supramolecular structure by strong hydrogen bonds and π–π stacking interactions.
Both complexes were characterized by physico-chemical and spectroscopic methods. 相似文献
115.
本文报道酸性媒染紫(SVRS)一示波计时电位法测定天然水中不同形态铝。对24个实际水样分别在酸性pH5.2测定了无机单核铝Ali和碱性pH8.8底液中测定总单核铝Ala,有机单核铝Al0-Ala-Alio同时还应用该法测定了酸化水样中总铝AlT,酸溶态铝AlT=AlT-Ala,从而实现了水样中五种形态铝的电化学测定,测定值与Driscoll方法进行了比较对照,结果基本一致。本法特点为:简便快捷,灵敏准确,可以直接测定与铝毒性密切相关的无机单核铝Ali,无需分离步骤,水样用量小,适用于大批量天然水样中Al形态的快速分析。 相似文献
116.
117.
Terbium p-chlorobenzoate complex with 1,10-phenanthroline, [Tb(p-ClBA)3(phen)]2(1) has been obtained in the ethanol solution, where p-ClBA=p-chlorobenzoate and phen=1,10-phenanthroline. It crystallizes in the triclinic system, space group P1, a=1.008 1(2) nm, b=1.185 7(2) nm, c=1.431 1(3) nm, α=110.826(4)°, β=96.436(4)°, γ=101.737(4)°, Z=2. The two Tb(III) ions are linked by four carboxylate groups through their bidentate bridging modes, forming a dimeric unit with crystallographic inversion center. Each terbium ion has an eight-coordinate geometry with four of the coordination sites occupied by four oxygen atoms from the four bridging carboxylates, respectively, two oxygen atoms from bidentate carboxylate, and the remaining positions occupied by two nitrogen atoms from a 1,10-phenanthroline molecule. The Tb(III) ion adopt a distorted square antiprism coordination geometry. The excitation and luminescence data observed at room temperature show that the title complex emits very intensive green fluorescence under ultraviolet light. The result of thermal analysis indicates the complex [Tb(p-ClBA)3(phen)]2 is quite stable to heat. CCDC: 221921. 相似文献
118.
A very sensitive and selective analytical method for the determination of trace levels of aluminum in the natural waters is presented in this paper. It is based on the adsorption chronopotentiometry in the presence of rubeanic acid (RA). Complexation of Al by RA is rapid and the procedure of heating sample or waiting is not required. 相似文献
119.
三元系RbCl-C2H5OH-H2O液固相平衡及其物化性质研究 总被引:2,自引:0,他引:2
The isothermal solubility and physico-chemical properties (density, refractive index) of ternary system RbCl-EtOH-H2O at 25℃ and 50℃ have been firstly investigated by means of self-made micro-equilibrium and sampling apparatus .The compositions of liquid and solid at equilibrium state were determined, and the problem of analysis of ethanol content in system was properly solved. The phase diagram was drawn by the TPD phase-diagram computer program developed by us. Three empirical formulae were proposed to correlate the solubility, density and refractive index respectively. No demixing phenomena was observed in the range of temperature related in this study. 相似文献
120.
研究了合成温度对Tyr(酪氨酸)/LDH(层状双氢氧化物)纳米复合物性质的影响. 结果表明: 随着合成温度的升高, 纳米复合材料的层间距和比表面积逐渐降低; 随着温度的升高, 合成粒子的形状由球形到三角形最后变为无定形. 进一步的研究表明, 这些规律性的变化与插入层间的生物分子数量有关. 相似文献