UPLC-QTOF-MS法研究甘油三酯作为水生环境中农药污染的潜在生物标志物

以鲫鱼为代表性研究对象, 采用超高效液相色谱-四极杆飞行时间质谱(UPLC-QTOF-MS)技术, 分别研究了3种农药(敌百虫、 高效氯氰菊酯和吡虫啉)对其体内代谢的影响. 通过Masslynx软件在MS ^E模式下采集数据, 使用UNIFI软件进行自动检测和数据过滤, 并将差异性物质与在线代谢组数据库进行比较, 鉴定出甘油三酯类(TGs)物质具有明显差异. 其中, 吡虫啉对TGs代谢的影响最大, 且肝脏的代谢差异比大脑更显著, 低浓度的急性暴露诱导肝脏中的TGs积累, 其含量与暴露浓度之间的关系符合Michaelis-Menten方程的增长趋势. 结果表明, TGs可在短时间内(≤2 h)灵敏地反映农药吡虫啉的低浓度(≤20 ng/mL)暴露, 可作为考察吡虫啉对水生生物毒性的潜在生物标记物, 有助于建立一种快速、 灵敏的预警方法.     

高效液相色谱-电喷雾离子阱串联质谱法检测芥子气经皮肤染毒SD大鼠肺中的DNA加合物

运用高效液相色谱-电喷雾离子阱串联质谱(HPLC-ESI-MS/MS)技术,建立了快速、简单、灵敏的SD大鼠肺中N7-(2-羟乙基硫代乙基)鸟嘌呤(N7-HETEG)的检测方法。以N7-苯甲基鸟嘌呤为内标,用甲醇和水为流动相进行梯度洗脱,正离子模式检测,方法的检出限(信噪比(S/N)≥10)为300 pg/mL,定量限(S/N≥20)为850 pg/mL。在300 pg/mL～1.28 μg/mL的质量浓度范围内,N7-HETEG浓度与N7-HETEG和内标的峰面积比呈良好的线性关系(线性相关系数为0.9929)。高、中、低3个添加水平的日内测定精密度(以相对标准偏差(RSD)计)和日间测定精密度均小于10%(n=7),回收率为100%～132%。对SD大鼠背部皮肤染芥子气,剂量分别为5.5、11、22和45 mg/kg,染毒4 d后检测大鼠肺脏中N7-HETEG的含量。各个不同染毒剂量下,每克组织中分别检测到（0.56±0.16）、（0.67±0.12）、（1.36±0.68）和(5.14±0.92) ng N7-HETEG, N7-HETEG的含量随着染毒剂量的增大而增大,表明N7-HETEG可用作芥子气暴露的体内生物标志物。     

UPLC-MS/MS法快速筛查尿液中30种滥用药物

基于超高液相色谱-串联四极杆/线性离子阱质谱(QTRAP UPLC-MS/MS),建立了尿液中30种滥用药物的筛查方法。采用蛋白沉淀法处理尿液样品,实现对多类别滥用药物的高效提取。采用分段多反应监测(s MRM)联合信息依赖性采集(IDA)与增强离子扫描(EPI)模式,结合EPI谱库检索匹配确证检出物信息,并引入内标辅助定量。30种滥用药物质量浓度在0.5~50 ng/mL范围内线性关系良好(R²> 0.99);检出限为0.01~0.25 ng/mL,定量限为0.1~0.4 ng/mL;加标回收率为76.2%~112.5%,相对标准偏差为3.1%~12%。该方法适用于实际尿样中痕量滥用药物的定性与定量分析。     

固相萃取-气相色谱-质谱法检测染毒尿样中芥子气-谷胱甘肽加合物的β-裂解产物

合成并纯化了芥子气-谷胱甘肽的β-裂解产物1,1′-磺酰基二(2-甲巯基)乙烷(SBMTE),纯度为98.9%.建立了固相萃取-气相色谱质谱法检测染毒尿样中SBMTE的方法,对尿样中SBMTE的提取富集、 Oasis HLB固相萃取柱净化条件等因素进行了优化.实验中采用DB-5MS毛细管柱进行分离,以化学电离源(CI)质谱选择离子模式(SIM)进行检测,并通过内标法定量.SBMTE的线性范围为1～100 ng/mL,r=0.9991,回收率为89.0%～92.6%,检出限为0.5 ng/mL.方法满足芥子气中毒人群尿中SBMTE的检测要求.     

小儿肺炎患者尿液的代谢组学初步研究

利用液相色谱-质谱联用法对小儿肺炎( Childhood pneumonia, CP)患者和健康儿童( Healthy control)的尿液进行分析,发现小儿肺炎患者尿液中的潜在标记物,为其发病机制及早期筛查提供科学依据。筛选10例小儿肺炎患者(age 47.72±2.35 months)及10例健康儿童(age 46.65±1.97 months)尿液样本,采用快速高分辨液相色谱四极杆-飞行时间质谱联用( RRLC-Q TOF/MS)技术对其尿液代谢物进行分析,通过主成分分析方法( PCA)对两组代谢物进行分类,并发现潜在生物标记物。 RRLC-Q TOF/MS检测表明,CP组和Healthy Control组尿液代谢物图谱能得到很好的区分,并鉴定了5种生物标记物,提示嘌呤代谢、氨基酸代谢可能在小儿肺炎发生发展中有重要作用。     

基于HPLC/Q-TOF MS的4种农药联合暴露人群的代谢组学研究

采用基于高效液相色谱-飞行时间质谱联用(HPLC-TOF MS)的代谢组学方法,研究了啶虫脒、高效氯氟氰菊酯、联苯菊酯、甲氨基阿维菌素苯甲酸盐4种农药联合暴露所致的施药人群尿液中内源性代谢物的变化。采集30位农民喷洒4种复合农药前和喷洒农药期1,3,5,7 d的尿液进行检测。提取正常尿液中常见代谢物并通过质控样品评价手段进行分析,结果表明该方法具有良好的稳定性和精密度,可用于尿液中代谢物分析。多变量分析结果表明,暴露人群施药前后尿液的代谢物含量存在较大差异。对选取的36个差异离子进行鉴定,确定了8个生物标志物的结构。结果显示联合暴露组人群尿液中多巴胺、5-羟色胺、酪氨酸、色氨酸、牛磺酸和马尿酸的含量显著下降;犬尿素和肌酸的含量显著上升。4种农药联合暴露导致接触人群尿液中色氨酸代谢途径的中间产物含量降低,肝代谢和能量代谢相关的代谢物蓄积,可能与神经系统和肝脏功能的受损有关。     

暴露于环境烟气中的大鼠尿样代谢物分析

4-(甲基亚硝胺基)-1-(3-吡啶基)-1-丁醇(NNAL)是烟草特有亚硝胺4-(甲基亚硝胺基)-1-(3-吡啶)-1-丁酮(NNK)在生物体内的一种代谢标记物,分析暴露于烟气中的生物体内NNAL的含量是研究卷烟烟气对生物体健康影响的有效手段.基于人体的个体差异性很大,本文以饲养的大鼠为研究对象,采用LC-MS/MS...     

高效液相色谱-三重四极杆复合线性离子阱质谱法检测血液中8种苯二氮卓类药物

建立了血液样本中8种苯二氮卓类药物的高效液相色谱-三重四极杆复合线性离子阱质谱(QTRAP HPLC-MS/MS)检测方法。血液样本经乙腈沉淀蛋白法处理,离心取上清液,过滤后采用分段多反应监测结合信息依赖性采集与增强离子扫描(sMRM-IDA-EPI)模式分析,结合EPI二级谱库检索确证可疑检出物,以sMRM数据采用外标法定量检测。8种苯二氮卓类药物在0.5~50 ng/mL范围内线性关系良好(r>0.998);检出限为0.01~0.10 ng/mL,定量下限为0.10~0.25 ng/mL;化合物在1.0、5.0、20 ng/mL 3个加标水平下的回收率为79.3%~112%,基质效应为79.8%~97.2%,相对标准偏差为4.3%~11%。该方法操作简便,结果准确,适用于中毒患者病情的快速确诊与评估,可为医疗急救与中毒检测提供技术支持。     

液相色谱-串联质谱法同时检测乙醛-DNA加合物

本文建立了一种同时检测DNA样品中Ethylidene-dG和Propano-dG含量的液相色谱-串联质谱(LC-MS/MS)方法,方法的精密度较好(RSD6%),检出限分别为0.010ng/mL和0.005ng/mL,回收率在97.2%~101.6%之间。同时,以体外小牛胸腺DNA为模型,选取不同乙醛暴露剂量(0、0.001、0.01、0.05、0.1、0.5和1.0mmol/L)和不同的暴露时间(0、2、4、10、12、20和24h),结果显示在体外Propano-dG加合物的生成需有氨基酸作为催化剂,且小牛胸腺DNA中乙醛-DNA加合物的含量随着染毒剂量和染毒时间的增加而升高,存在剂量-效应和时间-效应关系。     

超高效液相色谱-串联质谱法快速同步测定人血中35种毒（药）物及主要代谢产物

建立了超高效液相色谱-串联质谱法（UPLC-MS/MS）快速测定人血中常见35种毒（药）物及主要代谢产物的方法。取1 mL血液样品,加入5颗研磨珠、40 mg（NH₄）₂SO₄、1.5 mL乙腈进行提取,涡旋振荡60 s,静置60 s,冷冻离心后取上清液体过0.22μm有机滤膜后进行分析。结果表明,目标化合物在10～1000 ng/mL质量浓度范围呈良好的线性关系（R²为0.9921～0.9998）,检出限（S/N≥3）为0.05～2.00 ng/mL,目标毒（药）物定量限（S/N≥10）为20 ng/mL占比为17%,其余目标毒（药）物定量限均为10 ng/mL。在20,50和100 ng/mL加标浓度水平下,目标化合物回收率为71.5%～119.8%,日内相对标准偏差（Intra-RSD）为1.1%～13.8%。在50 ng/mL加标水平下,日间相对标准偏差（Inter-RSD）为2.6%～13.4%。该方法适用于血液中毒（药）物及代谢产物的快速分析测定。     

Monitoring urinary metabolites resulting from sulfur mustard exposure in rabbits,using highly sensitive isotope-dilution gas chromatography–mass spectrometry

A highly sensitive method for the determination of sulfur mustard (SM) metabolites thiodiglycol (TDG) and thiodiglycol sulfoxide (TDGO) in urine was established and validated using isotope-dilution negative-ion chemical ionization (NICI) gas chromatography–mass spectrometry (GC–MS). TDGO in the samples was reduced with TiCl₃, and then determined together with TDG as a single analyte. The sample preparation procedures, including two solid-phase-extraction (SPE) clean-up steps, were optimized to improve the sensitivity of the method. The limits of detection (LOD) for both TDG and TDG plus TDGO (TDG + TDGO) were 0.1 ng mL^?1, and the limits of quantitation (LOQ) for both were 0.3 ng mL^?1. The method was used in a rabbit cutaneous SM exposure model. Domestic rabbits were exposed to neat liquid SM at three dosage levels (0.02, 0.05, and 0.15 LD₅₀), and the urinary excretion of four species of hydrolysis metabolites, namely free TDG, free plus conjugated TDG (total TDG), free TDG + TDGO, and free plus conjugated TDG + TDGO (total TDG + TDGO), was evaluated to investigate the metabolic processes. The total urinary excretion profiles of the metabolites, including the peak time, time window, and dose–response and time–response relationships, were clarified. The results revealed that the concentrations of TDG and TDG + TDGO in the urine increased quickly and then decreased rapidly in the first two days after SM exposure. The cumulative amount of total TDG + TDGO excreted in urine during the first five days accounted for 0.5–1 % of the applied dose of SM. It is also concluded that TDG and TDGO in urine existed mainly in free form, the levels of glucuronide and of sulfate conjugates of TDG or TDGO were very low, and most hydrolysis metabolites were present in the oxidized form (TDGO). The study indicates that the abnormal increase of TDG and TDGO excretion levels can be used as a diagnostic indicator and establishes a reference time-window for retrospective analysis and sampling after SM exposure.     

多环芳烃暴露的生物标志物——尿中羟基多环芳烃

多环芳烃(PAHs) 是典型的持久性有机污染物,在职业高PAHs 暴露环境下,容易诱发肺癌、皮肤癌等癌症。对PAHs 的暴露评价可为流行病学研究和污染物风险评价等提供有效的数据。由于暴露途径的复杂化,采用尿样中PAHs 的代谢产物———羟基多环芳烃作为标志物来综合评价人体对PAHs 的内暴露情况已经成为研究的热点。本文系统介绍了多环芳烃的吸收、代谢、尿中PAHs 代谢产物的主要存在形式、主要的生物标志物以及它们的主要影响因素。     

Extraction of thiodiglycol from soil using pressurised liquid extraction

Thiodiglycol (TDG) is the predominant hydrolysis product of the chemical warfare agent sulfur mustard. The extraction of TDG was investigated using pressurised liquid extraction and the results compared for a variety of different solvents and soils. TDG was analysed underivatised by gas chromatography with flame photometric detection. A mixture of methanol-water (9:1), proved to be the most efficient extracting solvent for TDG at a temperature of 150 degrees C and 10 MPa.     

超高效液相色谱-串联质谱法同时检测人血浆中6种芥子气染毒标识物

针对芥子气( HD)染毒血浆的溯源性分析需求,采用超高效液相色谱-串联质谱技术( UHPLC-MS/MS),建立了人血浆中6种HD生物标识物( TDG,TDGO,SMO,SBMSE,MSMTESE,SBSNAE)的高灵敏度和专属性检测方法。应用甲醇和乙腈混合有机溶剂沉淀HD染毒血浆中的蛋白,然后用HLB柱固相萃取( SPE)纯化,经超高效液相色谱梯度洗脱分离,在三重四极杆串联质谱正离子多反应监测( MRM)模式下进行定性与定量检测。结果表明,6种目标物的线性范围为0.05~500 ng/mL(R2=0.9840~0.9955),检测限在0.01~1.0 ng/mL之间,各分析物的精密度(n=5)≤5.5%,加标回收率在86.5%~110.8%之间。本方法通过SPE的引入和UHPLC程序的优化,有效地解决了基质背景对分析可靠性的影响问题,并成功应用于国际禁止化学武器组织( OPCW)第5次生物医学样品分析演练HD染毒血浆样品的鉴定。     

Simultaneous quantitation of urinary cotinine and acrylonitrile-derived mercapturic acids with ultraperformance liquid chromatography–tandem mass spectrometry

Acrylonitrile (AN), a widely used industrial chemical also found in tobacco smoke, has been classified as a possible human carcinogen (group 2B) by the International Agency for Research on Cancer. AN can be detoxified by glutathione S-transferase (GST) to form glutathione (GSH) conjugates in vivo. It can be metabolically activated by cytochrome P450 2E1 to form 2-cyanoethylene oxide, which can also be detoxified by GST to generate GSH conjugates. The GSH conjugates can be further metabolized to mercapturic acids (MAs), namely, N-acetyl-S-(2-cyanoethyl)cysteine (CEMA), N-acetyl-S-(2-hydroxyethyl)cysteine (HEMA), and N-acetyl-S-(1-cyano-2-hydroxyethyl)cysteine (CHEMA). This study developed an ultraperformance liquid chromatography coupled with tandem mass spectrometry (UPLC-MS/MS) method to quantitatively profile the major AN urinary metabolites (CEMA, HEMA, and CHEMA) to assess AN exposure, as well as analyze urinary cotinine (COT) as an indicator for tobacco smoke exposure. The limits of quantitation were 0.1, 0.1, 1.0, and 0.05 μg/L for HEMA, CEMA, CHEMA, and COT, respectively. This method was applied to analyze the three AN-derived MAs in 36 volunteers with no prior occupational AN exposure. Data analysis showed significant correlations between the level of COT and the levels of these MAs, suggesting them as biomarkers for exposure to low levels of AN. The results demonstrate that a highly specific and sensitive UPLC-MS/MS method has been successfully developed to quantitatively profile the major urinary metabolites of AN in humans to assess low AN exposure.     

Determination of thiodiglycol, a mustard gas hydrolysis product by gas chromatography-mass spectrometry after tert-butyldimethylsilylation

A method for determining thiodiglycol (TDG), a mustard gas hydrolysis product in water, serum and urine samples using gas chromatography-mass spectrometry (GC-MS) after tert-butyldimethylsilylation (TBDMS) is described. Quantitation of TDG was performed by measuring the respective peak area on the extracted ion chromatogram of m/z 293, using an internal standard, the TDG homologue, thiodipropanol, peak area of which was measured as m/z 321. The presence of salts in the sample solution not only suppressed the loss of TDG by vaporization during the evaporation of water, but also facilitated the rate of production of di-silylated derivative, bis(tert-butyldimethylsilyoxylethyl)sulfide (TDG-(TBDMS)2). Under the pretreatment conditions used, in which 0.5 ml of water sample supplemented with 100 microM potassium chloride was evaporated to dryness under reduced pressure, followed by reaction with N-methyl-N-(tert-butyldimethylsilyl)trifluoroacetamide at 60 degrees C for 1 h, TDG-(TBDMS)2 was reproducibly detected with about a 55% recovery and a limit of detection (LOD, scan mode, S/N = 3) of 5.4 ng/ml. TDG was also determined by GC-MS from a 0.5 ml serum sample (after perchloric acid deproteinization) and from a 0.1 ml urine sample, after TBDMS derivatization. The LOD was determined to be 7.0 and 110 ng/ml for serum and urine, respectively.     

Determination of the sulfur mustard hydrolysis product thiodiglycol by microcolumn liquid chromatography coupled on-line with sulfur flame photometric detection using large-volume injections and peak compression.

A selective, direct and relatively rapid method has been developed for the determination of thiodiglycol (TDG) in aqueous samples. TDG is the main hydrolysis product of the chemical warfare agent sulfur mustard. The method of analysis is based on the on-line coupling of reversed-phase microcolumn liquid chromatography and sulfur-selective flame photometric detection. To improve sensitivity and efficiency, peak compression by displacement was used in combination with large-volume injections. A concentration of 1% n-propanol was added to the sample to obtain the best sensitivity and efficiency after a 10 microliters injection. Detection limits of 0.25 microgram/ml were achieved with efficiencies of 4.10(5) plates per meter. The method was successfully applied during the Fourth Official Proficiency Test organized by the Technical Secretariat of the Organization for Prohibition of Chemical Weapons for the determination of TDG in a soil sample.     

Quantitative analysis of the sulfur mustard hydrolysis product thiodiglycol (2,2'-sulfobisethanol) in in vivo microdialysates using gas chromatography coupled with pulsed flame photometric detection

An analytical method employing gas chromatography is presented for assessing the concentrations of the sulfur mustard hydrolysis product thiodiglycol (TDG) in cutaneous in vivo microdialysates. The use of a pulsed flame photometric detector allows for selective detection of the analyte following solvent exchange and derivatization with heptafluorobutyric anhydride. Quantitative assessment is performed using thiodipropanol (TDP) as a surrogate internal standard. A linear relationship and a very significant correlation (r2 = 0.9982) between the ratio of TDG and TDP concentrations and the ratio of the square root of peak heights is demonstrated. The suitability of the analytical method is verified by the evaluation of blank in vivo microdialysates spiked with known amounts of TDG. The limit of detection in microdialysates is 0.200 nmol/mL (24.4 ng/mL) and the limit of quantitation was 0.364 nmol/mL (44.4 ng/mL). The presented method provides selective, sensitive, rapid, and high-throughput analysis of microdialysates containing TDG, providing an efficient alternative for high-performance liquid chromatography and capillary electrophoresis techniques.     

人体邻苯二甲酸酯暴露的尿液生物标志物分析方法

邻苯二甲酸酯（phthalates，PAEs）是一类典型的环境内分泌干扰物。近年来，由于PAEs产量和使用量的增加，其对人体健康的危害尤其是生殖发育毒性受到了人们高度关注。由于PAEs在环境、食物（材）中广泛存在，导致人体不可避免地长期暴露于PAEs化合物，因此很有必要开展人体PAEs暴露评估。对人体尿液样品中的PAEs代谢物进行筛选和定量是评价PAEs暴露的重要手段，而建立它们准确、可靠的分析方法是重要前提。目前，邻苯二甲酸单酯和次级代谢物分别是短链和长链PAEs暴露最为常用的生物标志物。离线或在线固相萃取与高效液相色谱-串联质谱联用已成为测定PAEs代谢物的首选方法。本文主要综述了人体PAEs暴露的尿液生物标志物的分析方法，并讨论了这些方法在实际应用中的优点、局限性及挑战。