超高效液相色谱-串联四极杆质谱法测定水产品中氯霉素残留量

建立超高效液相色谱-串联四极杆质谱法测定水产品中氯霉素残留量的方法。样品均质后经乙酸乙酯提取,正己烷脱脂(或用固相萃取柱净化),超高效液相色谱分离,串联四级杆质谱检测,同位素内标法定量。方法在0.05～1.0μg/kg的添加范围内的平均回收率为84.9%～103.3%,相对标准偏差为3.2%～5.2%,定量检测限为0.02μg/kg。方法适用于各种水产品基质的氯霉素残留检测。     

UPLC-MS-MS快速分析烟草中的农药残留

采用基质分散固相萃取净化、超高效液相色谱分离与串联质谱检测建立了烟草中50种农药及其代谢物残留的分析方法。在0.02~0.50 mg/kg添加水平下,50种农药的回收率在68.3%~102.3%之间,相对标准偏差在2.1%~7.5%之间,定量限为4~15μg/kg。     

气相色谱-质谱联用法测定紫菜中扑草净的残留量

建立了固相萃取净化与气相色谱-质谱联用技术测定紫菜中扑草净除草剂残留量的检测方法。样品由乙腈溶剂提取浓缩后,活性炭和氨基柱双柱串联固相萃取净化,由气相色谱-质谱联用技术测定。方法定量限为2μg/kg,满足国外最低10μg/kg的限量要求;方法在10,40和100μg/kg 3个添加水平和不同人员操作条件下,回收率均稳定在90%~120%之间,RSD%≤7.1%。     

液相色谱串联质谱法测定鸡蛋中喹诺酮类药物残留

建立了鸡蛋中8种喹诺酮类残留的高效液相色谱串联质谱检测方法。样品用EDTAM cllvaine缓冲液提取,正己烷脱脂后,经HLB固相萃取柱净化,用LC-M S/M S进行检测,内标法定量。8种喹诺酮药物含量在0.5~50μg/kg浓度范围内线性关系良好,相关系数(r)均大于0.999。方法检出限为0.1~0.5μg/kg,定量限为0.3~1.7μg/kg,加标回收率为81.8%~118.4%,相对标准偏差均小于9.6%。该方法适用于鸡蛋中喹诺酮类药物残留量的检测。     

高效液相色谱-串联质谱法同时测定水产品中四环素类抗生素及盐酸克伦特罗药物残留量

建立了水产品中四环素类抗生素和盐酸克伦特罗药物残留量同时测定的高效液相色谱-串联质谱方法。样品选择NH4Ac缓冲液提取,用正己烷脱脂,PCX固相萃取柱净化,采用HPLC-MS/MS选择反应监测正离子模式测定进行定性、定量分析。四环素类抗生素和盐酸克伦特罗药物的检出限为0.25μg/kg,定量限为0.5μg/kg,RSD为1.9%~12%(n=6),加标回收率达到64.3%~100.6%。该方法在水产品中四环素类抗生素和盐酸克伦特罗的残留测定中具有很好的应用前景。     

超高效液相色谱-串联质谱法测定水产品中13种磺酰脲类除草剂残留量

建立了水产品中13种磺酰脲类除草剂的固相萃取-超高效液相色谱-串联质谱(SPE-UPLC-MS/MS)检测分析方法。鲤鱼、南美白对虾、中华绒鳌蟹、文蛤和海参的可食部分经均质制成样品,样品采用乙酸乙酯提取、MAX固相萃取柱净化,在超高效液相色谱-电喷雾串联质谱仪多反应监测模式下测定,外标法定量。13种目标物在5.0~100.0μg/L浓度范围内线性良好,相关系数均大于0.995,检出限为1.0μg/kg,定量限为2.0μg/kg,加标回收率在75.4%~118.3%之间,相对标准偏差(RSD)为2.1%~14.5%。对养殖草鱼、鲤鱼、海参、南美白对虾、大菱鲆及市场购买的大闸蟹进行检测,13种目标物均未检出。对暴露于含氯吡嘧磺隆1.0 mg/L水体24、48和72 h后的中华绒鳌蟹可食组织进行检测,含量分别为6.20、12.1和16.6μg/kg。本方法稳定、可靠,对于基质复杂的水产品有良好的适应性,适用于水产品中13种磺酰脲类除草剂的同时测定。     

气相色谱法和液相色谱-串联质谱法测定水产品中敌敌畏残留量

建立了水产品中敌敌畏残留量检测的两种不同方法,比较了气相色谱(GC)与液相色谱-串联质谱(LC-MS/MS)检测方法的适用性。GC法检出限为3.0μg/kg,定量限为10.0μg/kg;LC-MS/MS法检出限为0.3μg/kg,定量限为1.0μg/kg。当敌敌畏添加水平在5.0~15.0μg/kg时,GC法方法回收率为75.0%~90.9%,相对标准偏差为2.8%~9.6%;LC-MS/MS法方法回收率为89.7%~98.1%,相对标准偏差为1.0%~5.0%。结果表明,应用GC与LC-M S/M S检测方法均能满足水产品中敌敌畏残留分析要求,但在不考虑实验成本的前提下,LC-MS/MS法更具有优势。     

高效液相色谱-串联质谱法测定蔬菜和水果中氟吗啉的残留量

建立了高效液相-串联质谱法(LC-MS/MS)分析蔬菜和水果中氟吗啉残留量检测的方法。通过氟吗啉光照实验,研究了氟吗啉顺反异构体转化规律。以醚菌胺为内标(I.S.),乙酸乙酯提取,经HLB(亲水-疏水净化住)固相萃取小柱净化并富集后,以液相色谱分离,采用质谱正离子多反应监测模式进行定量分析。方法定量限为0.05μg/kg;线性范围为0.05～25μg/kg;提取回收率为77.64%～92.83%;相对标准偏差均小于8.6%。本方法灵敏度高、选择性好,实际样品检测中的检出率达到70%;样品中最高残留量为1.83μg/kg,能满足蔬菜和水果中氟吗啉残留量检测要求。     

超高效液相色谱-串联质谱法测定牛肉中非衍生化的脱呋喃甲酰基头孢噻呋残留量

建立了牛肉中脱呋喃甲酰基头孢噻呋(DFC)的超高效液相色谱-串联质谱(UPLC-MS/MS)检测方法。牛肉样品经DTE-硼酸盐缓冲液提取,过HLB固相萃取小柱净化浓缩,甲醇洗脱,UPLC-MS/MS法测定,仪器检测程序总色谱时间仅为5 min。方法平均回收率为80.7%～89.6%;批内变异系数范围在5.2%～9.7%之间;批间变异系数范围在6.1%～11.4%之间;检测限为0.55μg/kg;定量限为1.82μg/kg。方法可用于牛肉样品中脱呋喃甲酰基头孢噻呋药物残留量的确证检测。     

高效液相色谱-串联质谱测定水产品中残留的喹乙醇代谢物

建立了高效液相色谱-质谱(LC-MS/MS)检测水产品中喹乙醇代谢物3甲-基-喹恶啉-2羧-酸(MQCA)的残留分析方法。样品先用Protease蛋白酶酶解,然后用乙酸乙酯萃取目标物,氮气吹干后用流动相溶解残渣,以甲醇、乙腈和0.1%甲酸溶液作为流动相,液相色谱串联电喷雾质谱在正离子模式下测定。MQCA在1~100μg/kg范围内线性关系良好(r0.999)。在2、4、8μg/kg3个添加水平上,回收率在82.5%~87.5%,相对标准偏差为4.5%~5.1%(n=6),定量限为1μg/kg。方法已用于水产品中喹乙醇代谢物的残留分析。     

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...     

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.     

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.     

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.