气相色谱-质谱法分析膀胱癌患者尿液代谢组

建立了一种衍生化与气相色谱-质谱联用相结合的尿样代谢组分析方法.考察了样品预处理过程的提取溶剂、样品衍生化方法和气相升温梯度等分析条件,最终选择了丙酮为提取溶剂,V(MSTFA)∶ V(TMCS)=100∶ 1作为衍生化试剂.该方法线性良好(r2＞0.9916);制样精密度RSD小于15%,回收率在80.4%～117.9%之间.本法已成功应用于膀胱癌患者与正常人的尿液代谢组学分析,发现4种潜在的生物标记物.     

3,4-二巯基甲苯衍生化法结合SPME/GC-MS技术分析尿样中超痕量氯乙烯基胂酸

选取氯乙烯基胂酸(CVAOA)为生物标志物,建立了路易氏剂染毒尿样中超痕量CVAOA的分析方法。采用正交试验,优化了CVAOA的巯基化衍生方法,选取3,4-二巯基甲苯(DMT)作为衍生试剂,CVAOA与DMT的用量摩尔比为1∶1 000,常温衍生5 min,可达到最高的衍生效率;之后在优化的顶空-固相微萃取(HS-SPME)条件下富集纯化衍生产物CVAOA-DMT;使用气相色谱-质谱/选择离子监测模式(GC-MS/SIM)进行定性定量分析。该方法在50.0 pg/m L~500 ng/m L浓度范围内呈良好的线性(r2=0.998 5),相对标准偏差(RSD)小于10%,检出限可达7.6 pg/m L,定量下限为23 pg/m L。对低、中、高3种浓度的路易氏剂染毒尿样进行检测,回收率为97.6%~105%,RSD为4.4%~7.1%。该方法分析灵敏度高,具有良好的准确度、精密度和普及性,可被广泛推广和使用。     

高效液相色谱法同时测定肿瘤患者尿中假尿苷和肌酐的含量

An HPLC method for the simultaneous determination of pseudouridine(Pu)and Cretinine(C)in urinewas established;The recoveries of Pu and C were 92. 09±3.5%and 83. 01±5.7%respectively. The calibra-tion curves were linear within the concentration range of 2～200μg/mL for Pu and 5～300μg/mL for C. The detection linilts for Pu and C were 2. 15μg/mL and 4.75μg/mL. The method is rapid,sensitive and reliable.     

Monitoring of the influence of long‐term oxidative stress and ischemia on the condition of kidneys using solid‐phase microextraction chemical biopsy coupled with liquid chromatography–high‐resolution mass spectrometry

The limiting factor in conventional quality assessments of transplanted organs, namely the invasiveness of tissue sample collection, has prompted much research on the field of transplantology to focus on the development of alternative evaluation methods of organ quality. In the present project, we undertake the challenge to address the need for a new analytical solution for graft quality assessments by using a novel metabolomic diagnostic protocol based on low‐invasive solid‐phase microextraction. Solid‐phase microextraction probes of ca. 0.2 mm coated with 4 mm long mixed‐mode extraction phase were inserted into rabbit kidneys immediately following euthanasia and after 2, 4, 6, and 21 h of preservation. Liquid chromatography–mass spectrometry analysis of the extracts was performed with the use of a reversed phase column and a Q‐Exactive Focus mass spectrometer operated in positive ionization mode. Statistical analysis of significantly changing compounds revealed metabolic profile changes in kidneys induced by ischemia and oxidative stress as a function of the duration of cold storage. The most pronounced alterations were reflected in levels of essential amino acids and purine nucleosides. Our findings demonstrate that the proposed approach may be successfully used to monitor changes in the metabolic profile of organs over time of preservation.     

固相微萃取法结合GC-MS分析八角茴香中挥发性化合物

采用均相聚合物涂层———自制聚丙烯酸树脂(PA)萃取头,顶空萃取八角茴香中挥发性有机物.对萃取温度、样品量、解吸时间等参数进行了优化,得到了最佳萃取条件.该方法快速、简便,重现性好.通过气相色谱-质谱联用技术定性分析,鉴定了53种成分.同时,与商品多相聚合物涂层CAR/PDMS、DVB/CAR/PDMS分析结果比较,显示自制均相聚丙烯酸树脂萃取头对八角中挥发性有机物的萃取更全面.     

A Study on VOCs Released by Lung Cancer Cell Line Using GCMS-SPME

The gas chromatography mass spectrometry (GCMS) with combination of Solid Phase Micro-extraction (SPME) was used to study the volatile organic compounds (VOCs) which emitted by the in-vitro cultured human cells and compared with documented volatile biomarker of lung cancer. For this purpose, the lung cancer cell (A549) and non-cancerous lung cell (WI38VA13) were cultured in identical growth medium, concurrently. The VOCs in the headspace of the cell cultures and the blank growth media (reference sample) were collected directly from the culture flask using SPME for 15minutes. The results show that two different volatile metabolites were screened out between A549 cells and Wi38VA13 cells. A549 cell found to emit 2 noticeable VOC which are decane and heneicosane. While for WI38VA13, the VOCs released were 1-Heptanol and heptadecane. The acquired VOCs were compared with the previous studies. The findings in this work conclude that the specific VOC of cells can be act as their odour signature and can be used to provide non-invasively screening of lung cancer using gas array sensor devices.     

Determination of Trace Bisphenol A in Leachate by Solid Phase Microextraction Coupled with High Performance Liquid Chromatography

Abstract

A rapid determination method for trace bisphenol A in leachate by solid phase microextraction (SPME) coupled with high performance liquid chromatography (HPLC) was developed. The experimental condition of SPME, such as select operation, solid phase microextraction fibers, pH, extraction time, extraction temperature, desorption time, desorption solution, mode, and the analytical conditions of HPLC were optimized. As compared with the graph that was produced by HPLC alone, the graph by only HPLC couldn't analyze bisphenol A and compared to the results of three solid‐phase microextraction fibers. The linear range was between 0.0128 mg/L and 0.192 mg/L in this method, and the correlative coefficient was 0.9975. Limits of detection, repeatability, and reproducibility were also determined. The limit of detection of this method was 3.25 µg/L (3σ, n=11). The relative standard deviation (RSD, n=3) was 4.4%. The method was used for the determination of trace bisphenol A in leachate of Qingshan landfill and leachate of Liufang landfill. The recoveries were between 94.5% and 103.3%. This method is fast, convenient, sensitive, solvent free, and suitable for the determination of trace bisphenol A in leachate.     

液相微萃取-高效液相色谱法测定尿样中的利多卡因

应用液相微萃取与高效液相色谱联用技术快速分析尿样中的利多卡因。考察了萃取溶剂、体积、萃取时间及料液pH值对液相微萃取的影响,建立了液相微萃取与高效液相色谱联用技术分析尿样中利多卡因的方法。优化的实验条件为：料液pH值12．0,萃取溶剂为5μL邻苯二甲酸二丁醅,萃取时间40min,搅拌速度80r／min。方法的线性范围为0．2-5mg／L;检出限为0．1mg／L;相对标准偏差小于6．3％。通过液相微萃取后,能有效地去除检测尿样中利多卡因的干扰物质,获得了较高的选择性。该方法简便、快速、灵敏、消耗有机溶剂少,是尿样中利多卡因检测的一种有效方法。     

快速制备镍钛合金固相微萃取纤维及其与高效液相色谱联用测定环境水样中的紫外线吸收剂

以镍钛合金丝为基体,通过酸处理方法制得具有大比表面积的固相微萃取(SPME)纤维氧化物涂层。将其与高效液相色谱联用,研究了氧化物涂层对芳香分析物的萃取性能。结果表明,该纤维对所选择的紫外线吸收剂具有良好的萃取效率和选择性。进一步优化了紫外线吸收剂2-羟基-4-甲氧基二苯甲酮(BP-3)、2-乙基己基-4-甲氧基肉桂酸酯(EHMC)、4-(二甲氨基)苯甲酸-2-乙基己酯(OD-PABA)和2-乙基己基水杨酸酯(EHS)的萃取条件。方法在0.1~300μg·L~(-1)范围内具有良好的线性关系,检出限为0.025~0.097μg·L~(-1),使用单支SPME纤维同日内和隔日内的精密度分别为4.9%~5.8%和5.5%~6.4%,使用不同批次SPME纤维的精密度为6.3%~7.1%。所建立方法已成功用于环境水样中目标紫外线吸收剂的富集分离和测定。该纤维制作快速简单、稳定性高,不同批次制作的重现性好。     

Fecal Metabolic Profiling of Breast Cancer Patients during Neoadjuvant Chemotherapy Reveals Potential Biomarkers

Breast cancer (BC) is the most common form of cancer among women worldwide. Despite the huge advancements in its treatment, the exact etiology of breast cancer still remains unresolved. There is an increasing interest in the role of the gut microbiome in modulating the anti-cancer therapeutic response. It seems that alteration of the microbiome-derived metabolome potentially promotes carcinogenesis. Taken together, metabolomics has arisen as a fascinating new omics field to screen promising metabolic biomarkers. In this study, fecal metabolite profiling was performed using NMR spectroscopy, to identify potential biomarker candidates that can predict response to neoadjuvant chemotherapy (NAC) for breast cancer. Metabolic profiles of feces from patients (n = 8) following chemotherapy treatment cycles were studied. Interestingly, amino acids were found to be upregulated, while lactate and fumaric acid were downregulated in patients under the second and third cycles compared with patients before treatment. Furthermore, short-chain fatty acids (SCFAs) were significantly differentiated between the studied groups. These results strongly suggest that chemotherapy treatment plays a key role in modulating the fecal metabolomic profile of BC patients. In conclusion, we demonstrate the feasibility of identifying specific fecal metabolic profiles reflecting biochemical changes that occur during the chemotherapy treatment. These data give an interesting insight that may complement and improve clinical tools for BC monitoring.     

QSRR Study of GC Retention Indices of Volatile Compounds Emitted from Mosla chinensis Maxim by Multiple Linear Regression

The volatile compounds emitted from Mosla chinensis Maxim were analyzed by headspace solid‐phase microextraction (HS‐SPME) and headspace liquid‐phase microextraction (HS‐LPME) combined with gas chromatography‐mass spectrometry (GC‐MS). The main volatiles from Mosla chinensis Maxim were studied in this paper. It can be seen that 61 compounds were separated and identified. Forty‐nine volatile compounds were identified by SPME method, mainly including myrcene, α‐terpinene, p‐cymene, (E)‐ocimene, thymol, thymol acetate and (E)‐β‐farnesene. Forty‐five major volatile compounds were identified by LPME method, including α‐thujene, α‐pinene, camphene, butanoic acid, 2‐methylpropyl ester, myrcene, butanoic acid, butyl ester, α‐terpinene, p‐cymene, (E)‐ocimene, butane, 1,1‐dibutoxy‐, thymol, thymol acetate and (E)‐β‐farnesene. After analyzing the volatile compounds, multiple linear regression (MLR) method was used for building the regression model. Then the quantitative structure‐retention relationship (QSRR) model was validated by predictive‐ability test. The prediction results were in good agreement with the experimental values. The results demonstrated that headspace SPME‐GC‐MS and LPME‐GC‐MS are the simple, rapid and easy sample enrichment technique suitable for analysis of volatile compounds. This investigation provided an effective method for predicting the retention indices of new compounds even in the absence of the standard candidates.     

固相微萃取-气相色谱/质谱测定植物叶片中的挥发性物质

采用固相微萃取（SPME)方法吸附植物叶片中的挥发性物质,然后采用气相色谱/质谱法（GC/MS）分析了挥发性物 质的成分。在45 ℃水浴温度下,采用Polyacrylate(85 μm)固相微萃取头,在广口瓶中植物叶片的上方顶空吸附60 min,然后进行GC/MS分析。结果表明,植物叶片中的挥发性物质得到了很好的分离,受山楂叶螨(Tetraychus vienneis) 危害严重的植物的完好叶片中的挥发性物质均含有顺-3-己烯-1-醇乙酸酯、顺-3-己烯-1-醇丁酸酯和α-法呢烯,且含量 较大。初步确定这些物质是对山楂叶螨具有引诱作用的主要物质,从而为利用天然生物活性物质防治山楂叶螨提供了理论 依据。     

固相萃取/超高效液相色谱-串联质谱法测定尿液中6种双酚类及烷基酚类物质

建立了超高效液相色谱-串联质谱测定人体尿液中双酚A(BPA)、双酚F(BPF)、四氯双酚A(TCBPA)、四溴双酚A(TBBPA)、壬基酚(NP)、4-正辛基苯酚(4-n-OP)的检测方法。尿液样品通过酶解和固相萃取法进行前处理,采用Acquity UPLC HSS T₃色谱柱(2.1 mm×100 mm,1.8μm)分离,负离子电喷雾多反应监测模式检测,同位素内标法定量。6种待测物在0.5～50μg/L范围内线性关系良好,相关系数均大于0.995,检出限为0.05～0.60μg/L,定量下限为0.17～2.00μg/L,2、10、50μg/L加标水平下的回收率为81.4%～112%,相对标准偏差(RSD,n=6)为6.8%～30%。应用此方法测定160份人体尿液样品,双酚A的检出率为93.8%,检出范围为0.24～29.54μg/L,其余目标物未检出。该方法操作简便、重现性好、定量准确,适用于人体尿液中双酚类及烷基酚类物质的测定。     

分散液相微萃取/液相色谱串联质谱法快速测定猪尿中的盐酸克伦特罗与氯霉素

采用分散液相微萃取净化技术,建立了快速测定猪尿中盐酸克伦特罗和氯霉素残留的高效液相色谱-串联质谱分析方法.取5 mL猪尿样品,分别加入5 ngD9-盐酸克伦特罗和D5-氯霉素内标,调节pH至10.0,加入10％ NaC1,经250 μL三氯甲烷和750 μL异丙醇分散萃取后离心,转移下层沉淀,氮吹后以甲醇水溶液定容,采...     

顶空固相微萃取-气相色谱-质谱联用快速分析八角茴香中风味物质

采用顶空固相微萃取与气相色谱-质谱联用技术,对八角茴香中风味物质进行了分析。选用自制聚丙烯酸树脂涂层,对样品量、萃取时间、萃取温度、解吸时间等参数进行了优化,结果表明0．10g样品在60℃水浴中顶空萃取40min,250℃下解吸2min达到最佳条件。比较了顶空固相微萃取与传统水蒸气蒸馏两种前处理方法,分析结果非常相似。该方法可用于快速分析八角茴香中的风味物质。     

在线固相萃取/液相色谱-串联质谱法快速检测全血及尿液中15种杀鼠药

建立了同时测定血液和尿液样品中15种杀鼠药的在线固相萃取/液相色谱-三重四极杆串联质谱(On-line SPE/LC-MS/MS)分析方法。用乙腈沉淀样品中的蛋白质,经稀释、离心、过滤后直接进样。通过在线固相萃取柱HLB富集纯化,以ZORBAX Eclipse Plus C18柱为分析柱,乙腈-0.01 mol/L乙酸铵水溶液为流动相进行梯度洗脱。采用电喷雾电离(ESI+/ESI-)快速正负切换模式,动态多反应监测模式(DMRM)扫描,外标法定量。结果表明,15种杀鼠药采用二次方程拟合时线性关系良好,血液中r~2≥0.997 8,尿液r~2≥0.996 5,方法的检出限和定量下限分别为0.10~5.00μg/L和0.50~10.0μg/L,3个添加水平下的回收率为81.8%~109.6%,日内相对标准偏差(RSD)为0.3%~3.6%,日间RSD为0.3%~3.8%(n=6)。该方法简单方便,灵敏度高,能够用以血液和尿液样品中15种杀鼠药的快速筛查和准确定量。     

A rapid method for the quantification of urinary phthalate monoesters: A new strategy for the assessment of the exposure to phthalate ester by solid‐phase microextraction with gas chromatography and tandem mass spectrometry

In the following work, a new method for the analysis of the phthalate monoesters in human urine was reported. Phthalate monoesters are metabolites generated as a result of phthalate exposure. In compliance with the dictates of Green Analytical Chemistry, a rapid and simple protocol was developed and optimized for the quantification of phthalate monoesters (i.e., monoethyl phthalate, monoisobutyl phthalate, mono‐n‐butyl phthalate, mono‐(2‐ethylhexyl) phthalate, mono‐n‐octyl phthalate, monocyclohexyl phthalate, mono‐isononyl phthalate) in human urine, which entails preceding derivatization with methyl chloroformate combined with the use of commercial solid phase microextraction and the analysis by gas chromatography‐triple quadrupole mass spectrometry. The affinity of the derivatized analytes toward five commercial coatings was evaluated, and in terms of analyte extraction, the best results were reached with the use of the divinylbenzene/carboxen/polydimethylsiloxane fiber. The multivariate approach of experimental design was used to seek for the best working conditions of the derivatization reaction and the solid phase microextraction, thus obtaining the optimum response values. The proposed method was validated according to the guidelines issued by the Food and Drug Administration achieving satisfactory values in terms of linearity, sensitivity, matrix effect, intra‐ and inter‐day accuracy, and precision.     

移液枪头式固相微萃取-高效液相色谱法测定细胞培养液中的4种生物碱

建立了移液枪头式固相微萃取(SPME)-高效液相色谱检测细胞培养液中4种生物碱(黄柏碱、药根碱、巴马丁和小檗碱)的分析方法。以甲基丙烯酸为反应单体、乙二醇二甲基丙烯酸酯为交联剂、偶氮二异丁腈为引发剂,在移液枪头内进行原位聚合反应,制备含有弱阳离子交换整体固定相的SPME枪头。样品经SPME净化后,用高效液相色谱-紫外检测法进行分析,流动相为乙腈-磷酸二氢钾溶液(0.05 mol/L,pH 4),紫外检测波长为270 nm,外标法定量。4种生物碱的检出限(S/N=3)为0.16~0.39μg/L;以空白细胞培养液进行加标回收率试验,加标回收率为92.73%~97.91%,相对标准偏差(RSD)为0.14%~3.31%。该方法简单、灵敏、准确,能够用于细胞培养液中微量生物碱的分析研究。     

基于超高效液相色谱-高分辨质谱和渗透压校正样本浓度变异性的尿液代谢组学分析

尿液是代谢组学研究中主要关注的体液样本之一。尿液样本中的代谢物浓度受饮食、疾病等因素影响变异较大,这极大阻碍了高质量组学数据的获取和可靠生物标志物的鉴定。研究为克服尿液样本的浓度变异性,在原始数据采集前,根据样本渗透压的大小,针对性地调整进样量或者稀释样本,从而确保代谢组学分析样本的渗透压与进样量的乘积相当,再经超高效液相色谱-高分辨质谱技术(UPLC-HRMS)分析,采用总离子丰度或总有用峰面积(MSTUS)对数据集进行归一化处理。研究利用临床样本及其梯度稀释的溶液,对该方法与现有研究普遍使用的方法进行了比较,随后通过先天性肾积水患者及健康志愿者的尿液样本做了进一步的方法学验证。数据集经校正后,峰面积RSD<30%的提取峰数量增加,主成分分析结果较校正前有更高的组内聚集和组间分群效应,正交偏最小二乘判别分析的统计模型更不易过拟合。与肌酐比较,渗透压值与质谱信号间呈现了更好的线性关系。以上结果表明,数据采集前通过样本渗透压进行校正,能有效消除因样本本身代谢物浓度变化引起的组内差异,提高方法的重复性和统计模型的可靠度。以渗透压为基准的校正策略,比肌酐校正法适用范围更广,结果也更准确。研究可对后续各类来源的尿液代谢组学研究提供数据归一化的指导和参考。     

口腔癌患者尿液萘酚反应物的高效液相色谱荧光检测法筛查

利用高效液相色谱荧光检测法(HPLC/FLD)对口腔癌患者尿液中的萘酚反应物(NNR)进行分离分析,通过对34例口腔癌患者和18例健康人尿液的NNR进行分析,比较了癌症患者及健康人尿液中的成分含量差异,提出了一种可用于口腔癌辅助诊断的新方法。结果表明,在健康人及口腔癌患者尿液的萘酚反应物(NNR)中可检出一种标记物,其激发波长为440 nm,发射波长为539 nm。该标记物含量在口腔癌患者中较低,而在健康人群中显著偏高,这与通常的鉴定结果不同。通过采用非参数检验(Mann-Whitney U检验),该标记物含量在健康人群与口腔癌症患者中存在显著性差异(P0.01),其特异度为94.1%,敏感度为94.4%,ROC曲线下面积(AUC)为0.989。该模型具有较高的诊断价值,能够用于口腔癌的辅助鉴定。