离子色谱-质谱联用技术测定污泥样品中的痕量高氯酸盐

建立了离子色谱-质谱联用技术测定活性污泥样品中高氯酸盐的分析方法。以高容量、强亲水性的IonPacAS20(2mm)阴离子交换柱为分析柱,EGC在线产生等浓度KOH为淋洗液,淋洗液经抑制成水后将样品带入质谱检测。ESI-MS-MS以多元反应监测模式监控100.8/84.9、98.8/66.9、100.8/68.9和98.8/82.9离子对,以98.8/82.9离子对的峰面积进行定量。该方法对高氯酸盐的检出限(S/N=3)为0.01μg/L,高氯酸盐在0.05~100μg/L浓度范围内具有良好的线性,线性相关系数r=0.9988。0.2μg/L的标准溶液重复进样9次,高氯酸盐峰面积的相对标准偏差(RSD)为2.3%。运用该方法测定采自不同地区的活性污泥样品中的高氯酸盐,并对样品加标回收,得回收率在88.5%~102.2%之间。     

快速溶剂萃取-离子色谱-质谱法同时测定爆炸尘土中的氯酸盐和高氯酸盐EI北大核心CSCD

爆炸尘土用去离子水作为提取剂,萃取、离心和0.22μm滤膜净化后,采用Ion Pac AS20离子色谱柱分离,40 mmol/L KOH溶液等度淋洗,采用三重四极杆质谱仪负离子模式检测,多离子监测模式扫描,外标法定量。结果表明,氯酸盐和高氯酸盐在质量浓度0.5~100.0μg/L范围内,线性关系良好,相关系数均大于0.999。检出限分别为0.12和0.01μg/L,定量限为0.5μg/L和0.04μg/L,相对标准偏差为3.0%~5.0%和1.6%~5.0%,回收率范围为82.8%~86.5%和89.3%~93.2%。利用该方法测定爆炸尘土,所有样本均检出氯酸盐和高氯酸盐,含量范围分别为0.16~0.26 mg/kg和7.15~20.90 mg/kg。     

顶空进样GC-SIM-MS测定硝唑尼特中溶剂残留甲醇含量

利用气相色谱-选择离子监测质谱联用仪(GC-SIM-MS)测定硝唑尼特样品中溶剂残留甲醇的含量,顶空进样,温度为70℃,时间为20 min.SIM定量离子m/z 32,参考离子m/z 31,30和29.甲醇质量浓度在0.5~100μg/m L内呈良好的线性(R~2=0.999 92).方法相对标准偏差为2.49%~4.85%,样品加标回收在94.5%~102.8%之间,检测限为0.5μg/m L,符合定量分析的要求.     

离子色谱法测定乳粉中的高氯酸盐

建立了乳粉中痕量高氯酸盐的固相萃取离子色谱分析方法。在碱性条件下,乙腈提取、浓缩,0.22μm尼龙滤膜+RP柱净化,AS20阴离子分析柱(150mm×4.0mm)分离,流动相为氢氧化钠溶液(30~70mmol/L),流速1.0mL/min。结果表明,高氯酸盐在0.4~20μg/L内具有良好的线性关系,相关系数0.999 8,样品检出限20μg/kg,加标回收率在77.2%~108%。测定了41个乳粉中的高氯酸盐含量,高氯酸盐检出率为31.7%。对质监部门用来检测乳粉中高氯酸盐的方法是一个补充,为食品安全提供了参考数据。     

液相色谱-电喷雾离子阱质谱对芥子碱的测定方法

探讨了采用液相色谱-电喷雾串联质谱法检测小鼠前列腺中芥子碱硫氰酸盐的方法。流动相为V(乙腈)∶V(0.5%乙酸)=20∶80,色谱柱为ZorbaxXDB-C18(150 mm×4.6 mmi.d.,5μm),流速为0.6 mL/min。芥子碱硫氰酸盐的准分子离子和二级碎片离子分别为m/z 304和m/z 251,方法的检出限为0.7μg/L,线性范围为2.7~80.5μg/L,r为0.9934,相对标准偏差为7.5%~12.9%,样品的回收率为81.2%~102.5%。     

全自动SPE联合离子色谱质谱法测定化工产业园区周边地表径流中氟乙酸、碘乙酸、羟基乙酸、溴酸盐和高氯酸盐微量残留

目的 实验开发了全自动SPE联合离子色谱质谱法测定化工产业园区周边地表径流中氟乙酸、碘乙酸、羟基乙酸、溴酸盐和高氯酸盐微量残留的分析方法。方法 采集化工产业园区周边地表径流水样1000 mL,置试剂瓶中,去除肉眼可见杂质,滤纸过滤,调节水样PH至近中性;取上述水样500 mL,以流速12 mL/min的速度经固相萃取柱富集、净化,最后用10 mL甲醇溶液洗脱,合并收集的洗脱液,洗脱液置氮吹至近干,用1 mL甲醇溶液溶解残渣,0.22μm滤膜过滤,上离子色谱质谱仪定性、定量检测。结果 氟乙酸、碘乙酸、羟基乙酸、溴酸盐和高氯酸盐在浓度0.005 ~2.0μg/mL范围内,线性良好;检测限分别为0.021、0.023、0.0014、0.025和0.015 μg/L;三水平加标回收率在80%~120.6%范围内;精密度(RSD)在5.0%以内。结论 此方法检出限低、准确度和精密度好,适用于化工产业园区周边地表径流水样的检测分析。     

离子色谱-质谱联用技术测定饮用水及环境水样中的痕量高氯酸盐

建立了一种测定痕量高氯酸盐的离子色谱-质谱联用方法.选用高容量、强亲水性的阴离子交换柱IonPac AS20(2 mm)进行分离,以淋洗液自动发生器在线产生的KOH为淋洗液,采用等浓度淋洗.在不添加有机溶剂的情况下,淋洗液经过抑制器抑制后直接进入电喷雾-串联质谱(ESI-MS-MS),以负离子模式进行检测.同时采用多元反应监测(MRM)模式对高氯酸盐进行监控,以100.8/84.9、 98.8/66.9和100.8/68.9为监控离子对,以98.8/82.9离子对的峰面积进行定量.高氯酸盐质量浓度在0.05～50 μg/L范围内具有良好的线性(r＝0.9985),检出限(S/N=3)为0.01 μg/L.将该方法用于饮用水以及地下水、雪水等环境水样中高氯酸盐的分析,并进行了加标回收实验,回收率在86%～110%之间,将实际自来水样品连续11次进样,所得高氯酸盐的峰面积的相对标准偏差(RSD)为1.6%.     

大体积进样–Ag柱除氯–离子色谱法测定水中溴酸盐

建立以大体积进样(250μL)–离子色谱测定水中溴酸盐(BrO_3~–)的方法。采用Ag柱离线去除样品中大量Cl~–以消除Cl~–干扰,同时保证痕量溴酸盐未沉淀,过滤后直接进样测定。BrO_3~–的质量浓度在2.0~25.0μg/L范围内与色谱峰面积呈良好的线性关系,线性相关系数r=0.999 2,方法检出限为0.8μg/L。自来水和矿泉水样品3浓度水平加标回收率为85.0%~101.0%,测定结果的相对标准偏差为3.6%~12.9%(n=6)。该方法样品处理简单,检出限低,准确度和精密度高,满足分析测试的要求。     

离子色谱法同时测定蛋白胨中氯离子、硫酸根离子、碘离子

建立离子色谱法测定蛋白胨中氯离子、硫酸根离子、碘离子3种阴离子的含量。采用氢氧化钾淋洗液发生器产生的KOH溶液为流动相,进行梯度淋洗,流量为1.0 mL/min。氯离子、硫酸根离子的质量浓度分别在0.5～200μg/mL范围内与色谱峰面积呈良好的线性关系,碘离子的质量浓度在0.75～50μg/mL范围内与色谱峰面积呈良好的线性,线性相关系数均不小于0.999,检出限分别为0.003,0.01,0.22μg/mL。样品加标回收率为92.94%～96.59%,测定结果的相对标准偏差为2.42%～5.70%(n=9)。该方法灵敏、高效,可用于蛋白胨中氯离子、硫酸根离子、碘离子的快速准确测定。     

超高效液相色谱-电喷雾离子源-串联三重四极杆质谱分析饮用水中的高氯酸盐

建立了超高效液相色谱-电喷雾离子源-串联三重四极杆质谱(UPLC-ESI MS/MS)分析饮用水中高氯酸盐的方法.以300Extend-C18为分析柱,10%甲醇水溶液为流动相,ESI MS/MS串联质谱为检测器,以多重反应监测(MRM)模式监测高氯酸盐m/z 99.5→82.9离子对.方法的线性范围为0.2 ～10 μg/L,相关系数为r2=0.999 9,方法检出限为0.15 μg/L,平均加标回收率为82%,相对标准偏差为4.4%.应用UPLC-ESI MS/MS法测定北京市部分城区饮用水中的高氯酸盐,其中5个水样中检出ClO-4,质量浓度为0.040 ～0.262 μg/L,但在安全阈值范围内,不会对居民健康构成威胁.     

LC-ESI MS/MS测定蜜胺餐具中三聚氰胺的迁移量

建立了液相色谱串联电喷雾正离子源质谱(LC-ESI MS/MS)检测蜜胺餐具中三聚氰胺迁移量的方法.采用强阳离子交换柱,流动相为乙腈-10 mmol/L乙酸铵/乙酸缓冲溶液(pH 4.0)(40:60,体积比),以多反应离子监测对三聚氰胺做定性定量分析.在水、3%乙酸、10%乙醇模拟物中,三聚氰胺在3.00～130.0...     

Characterization of major degradation products of an adenosine A2A receptor antagonist under stressed conditions by LC‐MS and FT tandem MS analysis

Parkinson's disease (PD) is a very serious neurological disorder, and current methods of treatment fail to achieve long‐term control. SCH 420814 is a potent, selective and orally active adenosine A_2A receptor antagonist discovered by Schering‐Plough. Stability testing provides evidence of the quality of a bulk drug when exposed to the influence of environmental factors. Understanding the drug degradation profiles is critical to the safety and potency assessment of the drug candidate for clinical trials. As a result, identification of degradation products has taken an important role in drug development process. In this study, a rapid and sensitive method was developed for the structural determination of the degradation products of SCH 420814 formed under different forced conditions. The study utilizes a combination of liquid chromatography–tandem‐mass spectrometry (LC‐MS/MS) and Fourier Transform (FT) MS techniques to obtain complementary information for structure elucidation of the unknowns. This combination approach has significant impact on degradation product identification. A total of ten degradation products of SCH 420814 were characterized using the developed method. Copyright © 2009 John Wiley & Sons, Ltd.     

A Microcomputer Controlled Tandem Quadrupole Mass Spectrometer Using a Direct Liquid Introduction Probe for Screening Analysis

Abstract

The use of a direct liquid introduction probe with a short guard column as the method of sample introduction is explored. This technique is an alternative to the conventional direct probe method. The method is rapid, involatile compounds can be analyzed, and volatile compounds are not lost in the vacuum lock. Screening for trichlorophenol in urine, by observing the loss of [M-HCOCI]⁺, is used to test the technique. The advantages and disadvantages of split and splitless direct liquid introduction probes and column concentration are discussed. Detection limits in the low nanograms were observed, and samples may be analyzed every 30 seconds.     

Basic drug analysis by strong cation-exchange liquid chromatography-tandem mass spectrometry: simultaneous analysis of amisulpride, and of metamfetamine and amfetamine in serum/plasma

In the HPLC of basic drugs and metabolites, good efficiency and peak shape can often be attained using strong cation‐exchange packings with isocratic 100% methanol eluents containing an ionic modifier at an appropriate pH* and ionic strength. Solvent extracts can be analysed directly, and use of ammonium acetate as modifier facilitates the use of atmospheric pressure chemical ionization (APCI)–tandem mass spectrometry, selected reaction monitoring mode. For the analysis of amisulpride and of metamfetamine/amfetamine in plasma (200 µL) after single oral doses in man, a column packed with Waters Spherisorb S5SCX (5 µm average particle size, 100 × 2.1 mm i.d.) was used with methanolic ammonium acetate (40 mmol/L, pH* 6.0, flow rate 0.5 mL/min) as eluent (35°C). Deuterated internal standards were used for each analyte. Detection was by positive‐mode APCI. Responses for all analytes were linear over the calibration ranges. Intra‐assay precision (RSD) was 2–18%, and inter‐assay precision was 2–12%. The limit of detection was 0.5 µg/L for all analytes. No significant matrix effects or isobaric interferences were noted. The total analysis time was 7 min. Similar methodology can be applied to a wide range of basic analytes using MS/MS detection. Copyright © 2010 John Wiley & Sons, Ltd.     

乳腺癌代谢物组模式特征发现方法及HPLC/M S/M S分析

提出一种基于单独最优特征组合和BP神经网络的代谢物组模式特征发现方法,并用其寻找到尿样中与乳腺癌最为相关的4种核苷,组成一组特异性检测参数.经HPLC/MS/MS联用法鉴定,它们是乳清酸核苷、1-甲酰化腺苷、S-腺苷-L-蛋氨酸及N²-甲酰化鸟苷.将这4种核苷作为输入变量,用BP神经分类网络建立乳腺癌诊断模型.留一法交叉验证和独立验证结果表明,该模型预测准确率达到90%以上.     

LC/MS/MS for identification of in vivo and in vitro metabolites of jatrorrhizine

The in vivo and in vitro metabolism of jatrorrhizine has been investigated using a specific and sensitive LC/MS/MS method. In vivo samples including rat feces, urine and plasma collected separately after dosing healthy rats with jatrorrhizine (34 mg/kg) orally, along with in vitro samples prepared by incubating jatrorrhizine with rat intestinal flora and liver microsome, respectively, were purified using a C(18) solid-phase extraction cartridge. The purified samples were then separated with a reversed-phase C(18) column with methanol-formic acid aqueous solution (70:30, v/v, pH3.5) as mobile phase and detected by on-line MS/MS. The structural elucidation of the metabolites was performed by comparing their molecular weights and product ions with those of the parent drug. As a result, seven new metabolites were found in rat urine, 13 metabolites were detected in rat feces, 11 metabolites were detected in rat plasma, 17 metabolites were identified in intestinal flora incubation solution and nine metabolites were detected in liver microsome incubation solution. The main biotransformation reactions of jatrorrhizine were the hydroxylation reaction, the methylation reaction, the demethylation reaction and the dehydrogenation reaction of parent drug and its relative metabolites. All the results were reported for the first time, except for some of the metabolites in rat urine.     

Tandem mass spectrometry of synthetic polymers

The detailed characterization of macromolecules plays an important role for synthetic chemists to define and specify the structure and properties of the successfully synthesized polymers. The search for new characterization techniques for polymers is essential for the continuation of the development of improved synthesis methods. The application of tandem mass spectrometry for the detailed characterization of synthetic polymers using the soft ionization techniques matrix‐assisted laser desorption/ionization mass spectrometry (MALDI‐MS) and electrospray ionization mass spectrometry (ESI‐MS), which became the basic tools in proteomics, has greatly been increased in recent years and is summarized in this perspective. Examples of a variety of homopolymers, such as poly(methyl methacrylate), poly(ethylene glycol), as well as copolymers, e.g. copolyesters, are given. The advanced mass spectrometric techniques described in this review will presumably become one of the basic tools in polymer chemistry in the near future. Copyright © 2009 John Wiley & Sons, Ltd.     

动物源性食品中吡喹酮残留量的LC-MS/MS测定

应用固相萃取液相色谱-串联质谱法(LC-MS/MS)技术建立了动物源性食品中吡喹酮药物残留的检测方法。用乙酸乙酯提取样品中的吡喹酮残留,提取液经碱性氧化铝小柱净化,LC-MS/MS测定,在10~40μg/kg范围内添加回收率为91%~111%,定量下限(LOQ)为10μg/kg。本文还讨论了吡喹酮残留物的提取条件、流动相对吡喹酮ESI离子化的影响,并借助准MS/MS/MS技术探讨了吡喹酮主要质谱碎片的产生机理。     

Streamlined pentafluorophenylpropyl column liquid chromatography-tandem quadrupole mass spectrometry and global (13)C-labeled internal standards improve performance for quantitative metabolomics in bacteria

Streamlined quantitative metabolomics in central metabolism of bacteria would be greatly facilitated by a high-efficiency liquid chromatography (LC) method in conjunction with accurate quantitation. To achieve this goal, a methodology for LC-tandem quadrupole mass spectrometry (LC-MS/MS) involving a pentafluorophenylpropyl (PFPP) column and culture-derived global (13)C-labeled internal standards (I.Ss.) has been developed and compared to hydrophilic interaction liquid chromatography (HILIC)-MS/MS and published combined two-dimensional gas chromatography and LC methods. All 50 tested metabolite standards from 5 classes (amino acids, carboxylic acids, nucleotides, acyl-CoAs and sugar phosphates) displayed good chromatographic separation and sensitivity on the PFPP column. In addition, many important critical pairs such as isomers/isobars (e.g. isoleucine/leucine, methylsuccinic acid/ethylmalonic acid and malonyl-CoA/3-hydroxybutyryl-CoA) and metabolites of similar structure (e.g. malate/fumarate) were resolved better on the PFPP than on the HILIC column. Compared to only one (13)C-labeled I.S., the addition of global (13)C-labeled I.Ss. improved quantitative linearity and accuracy. PFPP-MS/MS with global (13)C-labeled I.Ss. allowed the absolute quantitation of 42 metabolite pool sizes in Methylobacterium extorquens AM1. A comparison of metabolite level changes published previously for ethylamine (C2) versus succinate (C4) cultures of M. extorquens AM1 indicated a good consistency with the data obtained by PFPP-MS/MS, suggesting this single approach has the capability of providing comprehensive metabolite profiling similar to the combination of methods. The more accurate quantification obtained by this method forms a fundamental basis for flux measurements and can be used for metabolism modeling in bacteria in future studies.