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基于Fe_3O_4磁性纳米粒子(MNPs)的QuEChERS预处理方法联合气相色谱串联质谱(GC-MS),建立了检测血液中多种苯二氮卓类药物的分析方法。利用QuEChERS提取法对血液样本进行预处理,处理过程中加入Fe_3O_4M NPs作为新型杂质吸附剂,采用外部磁铁进行两相分离,GC-MS法对多种苯二氮卓类药物进行快速定量检测。在最佳检测条件下,5种药物质量浓度在0.5~5.0μg/m L的范围内线性良好,r0.9872,检出限在0.103~0.412μg/m L之间。日内和日间相对标准偏差(RSD)均8.7%,方法的回收率在88.2%~113.2%之间。方法的分析性能能够满足临床对血液中药物检测的要求,在药物分析方面具有应用前景。 相似文献
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建立了低分辨气相色谱-负化学源质谱法(GC/NCI-LRMS)定性与定量检测母乳中的溴代/氯代阻燃剂及其代谢产物的方法。所检测的溴代/氯代阻燃剂及其代谢产物分为中性化合物和羟基化合物两部分。采用RTX-1614(30 m)作为色谱分离柱,在优化的色谱条件下对8种多溴联苯醚PBDEs(包括BDE209)及其甲氧基代谢产物MeO-PBDEs,多种其它阻燃剂及代谢物等中性化合物同时进行了分离检测;采用DB-5(30 m)作为色谱分离柱,在优化的色谱条件下分离检测了9种羟基多溴联苯醚OH-PBDEs。在母乳样本中加入代用标准或内标,经过超声提取、液液萃取、硅胶净化和浓缩定容等预处理后,分别对中性和羟基化合物进行测定。十溴联苯醚、其它多溴联苯醚、甲氧基多溴联苯醚、得克隆及脱氯产物、其它阻燃剂等中性化合物,及羟基多溴联苯醚在两个添加浓度水平的回收率分别为66.5%~75.4%,84.2%~126.4%,60.9%~115.1%,86.7%~104.9%,42.9%~113.8%和64.7%~129.5%;中性化合物的相对标准偏差均小于22%,羟基化合物的相对标准偏差均小于30%。利用本方法对我国电子垃圾拆解区人体母乳中的目标物进行了分析检测,结果可靠。 相似文献
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提出了由双泵单阀的驱动系统和双柱(预处理柱和分析柱)切换的分析系统所组成的色谱分析流程并应用于测定抗病毒口服液中非法添加物利巴韦林.样品离心后取上清液直接进样于C18预处理柱,水作为预处理流动相;用0.3 g·L-1磷酸二氢钠溶液(分析流动相)将保留在预处理柱上的药物冲入Kromasil C18分析柱(250 mm×4.6 mm,5μm)进行测定.方法集样品净化和色谱分析一次连续进行,测定条件下无干扰.检测波长205.6 am,药物的质量浓度在0.4~40.0 mg·L-1范围内呈线性(r=0.999 2),检出限(S/N=3)为0.08 mg·L-1,加标回收率分别为98.32%,98.45%,99.45%. 相似文献
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《理化检验(化学分册)》2011,(2)
《有害物质分析——仪器及应用》以有害化学物质检测为基础,内容主要包括各种实用仪器的应用,以及样品溶解、分离与富集等实用方法。本书共分三部分:第一部分为色谱/质谱分析,第二部分为光谱分析,第三部分为样品预处理及分 相似文献
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使用气相色谱-质谱法快速、简单、有效检测木制玩具中邻苯基苯酚的含量. 使用甲醇超声萃取,乙酸酐乙酰化对样品预处理,采用气相色谱-质谱技术进行检测. 研究结果显示,方法对邻苯基苯酚的检测线性范围为0.1~4.0 mg/L,检出限为0.01 mg/L,添加回收率为85%~101%,相对标准偏差为3.29%和3.52%. 表明方法不仅可以用于检测木制玩具中邻苯基苯酚,也可以用于其它材料中邻苯基苯酚的分析. 相似文献
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本文综述了第一代Dutch拆分、第二代Dutch拆分及反义Dutch拆分的拆分机理和研究进展,并展望了Dutch拆分的应用前景。Dutch拆分能以高收率和近于100%ee值与所有的实验消旋体迅速形成非对映体的结晶。第一代Dutch拆分中Family拆分试剂在形成非对映体晶体过程是典型的固溶体行为。在第二代Dutch拆分中,成核抑制剂改变了非对映异构体的亚稳区宽度,溶解度较大的非对映体盐比溶解度较小的非对映体盐的结晶温度下降得更多,使溶解度较小的非对映体盐更容易析出。 相似文献
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《Tetrahedron: Asymmetry》2000,11(19):3995-3999
A straightforward resolution of racemic methyl nonactate has been achieved by chromatographic separation of the corresponding d-mandelates followed by chemoselective hydrolysis of the mandelate ester function. Baker's yeast reduction of the ketone derived from racemic methyl nonactate proceeded with high enantioselectivity to give (+)-8-epi-methyl nonactate and (−)-methyl nonactate as alternative building blocks for macrotetrolide synthesis but was less efficient for the production of the latter compound. 相似文献
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Lennartson A Vestergren M Håkansson M 《Chemistry (Weinheim an der Bergstrasse, Germany)》2005,11(6):1757-1762
The crystal structures of [Pr(dbm)3H2O] (1), [Sm(dbm)3H2O] (2), and [Er(dbm)3H2O] (3) have been determined (dbm=dibenzoylmethane). They display seven-coordinate propeller-shaped molecules, which are chiral and crystallize as conglomerates in space group R3. Analysis of the crystal structures reveals supramolecular interactions, including formation of a quadruple helix, which explain how stereochemical information can be transferred between stacks of molecules. A method to quantify the ee in bulk samples of stereochemically labile compounds by using solid-state CD spectroscopy is described. Using this method, it has been shown that compounds 1-3 undergo total spontaneous resolution directly after synthesis, forming a microcrystalline reaction product that is essentially enantiopure. The resolution of bulk quantities of seven-coordinate complexes (without chiral or polydentate ligands) is thus reported for the first time. Because the crystallization starts without seeding, the overall preparation may be regarded as absolute asymmetric synthesis. 相似文献
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Erik Henke Sascha Schuster Hong Yang Uwe T. Bornscheuer 《Monatshefte für Chemie / Chemical Monthly》2000,131(6):633-638
Summary. The resolution of ibuprofen by transesterification of its corresponding vinylester using lipase B from Candida antarctica is described. Compared to transesterification or hydrolysis of the ibuprofen ethyl ester (E < 2, 28–48 h), the reaction with vinylesters occurred significantly faster (1.5–5 h) and with considerably higher enantioselectivity
(E = 8–39).
Received December 20, 1999. Accepted January 12, 2000 相似文献
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本文总结了手征性氟代醇、酸、胺、联苯类,由于分子过分拥挤而造成的不对称化合物及手征性全氟化合物的拆分。阐述了这项工作在生物化学、有机合成、有机分析以及有机反应机理的研究等方面的特殊意义。 相似文献
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《Tetrahedron: Asymmetry》1999,10(11):2175-2189
The (R)-enantiomer of albuterol has been isolated via resolution of albuterol acetonide with (2S,3S)-di-O-benzoyl- or (2S,3S)-di-O-toluoyltartaric acid. The absolute configuration of the resolved acetonide was assessed by 1H NMR analysis of its (R)-Mosher's ester, and confirmed by an X-ray crystal structure determination of the (R)-phenylethylurea derivative of the (S)-enantiomer. 相似文献
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Ferrocene derivatives especially the chiral and optically active 1,2-disubstituted ferrocenes are the most extensively investigated metallocenes. The common way to obtain the planar chirality in the ferrocene moiety is the usage of a chiral precursor. Sokolov et al have reported the asymmetric cyclopalladation with the salts of optically active carboxylic acids as nucleophilic catalysts, however, this method was suitable only when the reaction experienced the diastereomeric transition states[1]. The only report,of the resolution of cyclometallated ferrocene derivatives was given by Nonoyama and his coworkers[2]. They resolved dimethyl-aminomethylferrocene to optically pure enantiomers using the (S)-proline as chiral auxiliary and separated the diastereomers by solubility difference. 相似文献
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《Tetrahedron: Asymmetry》1998,9(22):4035-4041
The resolution of cycloplatinated ferrocenylketimines was carried out by using S-leucine as chiral auxiliary and a pair of diastereomers was obtained. The optically active derivatives of the cycloplatinated ferrocenylketimines have been prepared and characterized. The structures and absolute configurations of (−)-(Sp,S)-[Pt{(η5-C5H3CMeNC6H4-4-CH3)Fe(η5-C5H5)}(S-leu)] and (−)-(Sp)-[Pt{(η5-C5H3CMeNC6H4-4-Br)Fe(η5-C5H5)}(PPh3)Cl] were determined by X-ray diffraction, on the basis of which the absolute configurations of other optically active compounds studied were ascertained. 相似文献
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A resolution index for gel-permeation chromatograph (GPC) columns is defined by the relation log (RI) = αW, where RI is the resolution index, α is the slope of the calibration curve of logarithm of molecular weight against peak position for narrow polymer fractions, and W is the width of the GPC curves for narrow fractions. This resolution index is calculated approximately for several GPC columns individually and in series combinations by using data obtained on narrow fractions of polystyrene. The index increases with number of columns and with flow rate over a limited range of flow rate, does not vary much with solvent, and does not correlate well with plate count obtained with low molecular weight molecules. It is believed that the resolution index provides an improved indication of the performance of GPC columns. 相似文献