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31.
通过固相萃取-液相色谱-多级质谱(SPE-LC-MS/MS)联用技术和毒品胶体金免疫层析试剂盒检测法对13种中药及调味品样品中甲基苯丙胺及吗啡分别进行定量分析,依据LC-MS/MS检测结果,对毒品胶体金免疫层析试剂盒检测法进行可靠性评价。实验结果表明:型号1试剂盒对甲基苯丙胺和吗啡的特异性均不高,检测准确率分别为57.7%与78.8%;型号2试剂盒对甲基苯丙胺的特异性不足,准确率为73.1%,但对吗啡的检测准确率达到100%。在利用毒品胶体金免疫层析试剂盒进行毒品快速筛查时,应注重排除干扰因素以提高免疫胶体金层析试剂盒的检测准确度。 相似文献
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气相色谱-三重四极杆串联质谱法快速测定蔬菜水果中129种农药的残留量 总被引:5,自引:0,他引:5
采用QuEChERS方法结合气相色谱-串联质谱法(GC-MS/MS)建立了蔬菜、水果中129种农药残留同时检测的分析方法。试样用1%乙酸乙腈均质提取,采用混合型固相分散萃取剂净化后,用GC-MS/MS在多反应离子监测(MRM)模式下进行检测,外标法定量。结果表明,129种药物在一定的含量范围内线性关系良好,相关系数(r2)均大于0.98;不同基质在10 μg/kg添加水平下大部分农药的平均回收率为66.2%~124.7%,相对标准偏差(RSD)为0.9%~24.4%;方法的定量限(LOQ)为0.03~16.7 μg/kg。结果表明,该方法简便快速、灵敏可靠、经济有效,适用于蔬菜、水果中农药多残留的同时快速筛查测定。 相似文献
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1 INTRODUCTIONItwaswellknown thatelementsofthesecondary and higherrow are in generaldifficulty to form multiplebondsin which apπ hybridized stateisinvolved〔1〕.Thus,simple compounds containing multiple phosphorus carbon bonds,such as methyl dynephosphine( HC≡P) 〔2 - 3〕 and methylenephosphine( H2 C=PH〔4〕,are notstableat room temperature.Three methods to stabilize compounds containing double ormultiple bond involving phosphorusatom in the pπ hybridized state are often used.The f… 相似文献
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Xue Mei LUO Wei Jiang HE Yu ZHANG Zi Jian GUO Long Gen ZHU* State Key Laboratory of Coordination Chemistry Nanjing University Nanjing 《中国化学快报》2000,11(11)
Selectively chemical cleavage of peptides and proteins is one of the most important reactions in both chemical and biochemical processes. Over the past decade, the interaction of palladium(II) complexes with methionine, cysteine and histidine-containing peptides and proteins and the hydrolytic cleavage of the corresponding amide bond by Pd(II) complexes have been extensively studied1-13. However, reports concerning the directly selective hydrolysis of peptides and proteins with other simple … 相似文献
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Zhi NA Bei JIANG Hui YANG Zhong Wen LIN Han Dong SUN* Laboratory of Phytochemistry Kunming Institute of Botany Chinese Academy of Sciences Kunming Chemistry Deparment of the College of Life Science Chemistry Yunnan University K 《中国化学快报》2001,(8)
Isodon enanderianus (Hand. -Mazz.) H. W. Li, has been used in folk medicine as anti-inflammatory and detoxified agent1. The Isodon genus is known to be rich in ent-kaurane diterpenoids, a series of new ent-kaurane diterpenoids have been isolated from the dried leaves of I. enanderianus2-4. In order to find more biologically active substances, we have carefully investigated the chemical constituents of I. enanderianus collected in Shiping county of Yunnan province, and as a result, enanderi… 相似文献
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Mei Zhong JIN Li YANG Long Ming WU You Chen LIU Zhong Li LIU* National Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 《中国化学快报》2001,(4)
Reduction of C=N double bonds has been recognized as an important reaction both in organic chemistry and bio-chemistry1. Hantzsch 1,4-dihydropyridine (HEH, one of NADH model compounds) has been reported as a reductive reagent for imines2. However, application of dihydropyridines as practical reducing reagents in organic synthesis is limited because of their instability3. Like NADH models, 2-phenyl-N, N-dimethylbenzimidazoline (PDMBI) is an efficient electron and hydrogen donor (Eox = 0… 相似文献
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Retention Behaviors of Uronic Acid-containing Polysaccharides and Neutral Polysaccharides in HPGPC 总被引:2,自引:0,他引:2
Cui Ping LIU Xing Feng BAO Ji Nian FANG* Shanghai Institute of Materia Medica Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 《中国化学快报》2001,(10)
The determination of molecular weights (Mw) of polysaccharides has served as an important process since the physical properties of the polysaccharides are closely related to their Mw and/or molecular weights distribution (MWD). For Mw and MWD determinations, high performance gel permeation chromatography (HPGPC) has gained wide acceptance as a preferred method due to its high sensitivity, speed and reproducibility. In chromatography, it is well known that the molecular weights are determ… 相似文献
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Jia Rong Li~* Li Jun Zhang Xi Quan Yang Qing Li Dong Wang Chun Xia Wang Da Xin Shi Qi Zhang School of Chemical Engineering Environment Beijing Institute of Technology Beijing China 《中国化学快报》2008,(1)
Two different skeletons of heterocyclic compounds,quinoline and quinazolinone analogs could be obtained by a novel one-pot synthesis from substituted 3-amino-1 H-benzo[f]chromene-2-carbonitrile derivatives and cyclohexanone in DMF in the catalyst of anhydrous zinc chloride under reflux.A plausible mechanism was proposed. 相似文献