The measurement of urine catecholamine and metanephrine concentrations is important for biochemical screening and diagnosis of pheochromocytoma.The goal of this work was to develop a simple liquid chromatography-tande...The measurement of urine catecholamine and metanephrine concentrations is important for biochemical screening and diagnosis of pheochromocytoma.The goal of this work was to develop a simple liquid chromatography-tandem mass spectrometry(LC-MS/MS)method for determining catecholamines and metanephrines in urine to replace an existing liquid chromatographic method using electrochemical detection.Urine samples were prepared using Oasis weak-cation-exchange cartridges.The eluate was analyzed on an Agilent ZORBAX Eclipse Plus Phenyl-Hexyl column in 3 min.Adrenaline,noradrenaline,dopamine,metanephrine,normetanephrine,and their deuterated internal standards were monitored in positive electrospray ionization mode by multiple reaction monitoring(MRM).No evidence of ion suppression was observed.The assay was linear up to 5μmol/L for adrenaline,5μmol/L for noradrenaline,6.1μmol/L for dopamine,5.6μmol/L for metanephrine,and 34.6μmol/L for normetanephrine,with lower limits of quantification of 5,5,12,6 and 7nmol/L,respectively.The intra-day and inter-day precisions for all analytes ranged from 0.59%to 4.64%and1.98%to 4.80%,respectively.External quality assurance samples were assayed and showed excellent agreement with the target values.This simple method provides an improved assay for determining urine catecholamines and metanephrines.展开更多
In this experiment,a liquid chromatography tandem mass spectrometry method was built to determine 15 pesticide residues in Chinese cabbage and cucumber samples based on online turbulent flow chromatography purificatio...In this experiment,a liquid chromatography tandem mass spectrometry method was built to determine 15 pesticide residues in Chinese cabbage and cucumber samples based on online turbulent flow chromatography purification.After modified quick,easy,cheap,effective,rugged,and safe(QuEChERS)extraction,extracts were directly injected to the TLX(TurboFlow Liquid Xcalibur)system and brought to TurboFlow™columns for on-line purification and then transferred to analytical column for further separation and analysis.TurboFlow™columns types,transfer flow rate,and transfer time were optimized.Limits of detection and limits of quantification of the method obtained for 15 pesticide residues were ranged between 0.2–1.0μg/kg and 0.5–2.0μg/kg in Chinese cabbage and cucumber samples.Recoveries of pesticide residues were in range of 75.3%–103.7%.Matrix effects for 15 pesticides were in range of 5.6%–106.6%.The developed method has been successfully used for the determination of 15 pesticide residues in real samples.展开更多
Five thyreostats(TSs),namely tapazole,thiouracil,methylthiouracil,propylthiouracil,and phenylthiouracil,were determined in bovine urine using ultra-high performance liquid chromatography-tandem mass spectrometry(UHPLC...Five thyreostats(TSs),namely tapazole,thiouracil,methylthiouracil,propylthiouracil,and phenylthiouracil,were determined in bovine urine using ultra-high performance liquid chromatography-tandem mass spectrometry(UHPLC-MS/MS)in positive electrospray ionization mode.Extraction and clean-up were achieved using a ChemElut cartridge with tert-butyl methyl ether,without a derivatization step.Separation was achieved on an Acquity UPLC SS T3 column.The mobile phase was acetonitrile and water containing 0.2%(v/v)formic acid.The mass spectrometer was operated in multiple reaction monitoring mode.Urine samples were spiked with TS solution at levels corresponding to 5,10,15,and 20μg/L.The accuracy(internal standard corrected)ranged from 92%to 107%,with a repeatability precision(relative standard deviation,RSD)less than 15%for all five analytes.The RSDs within-laboratory reproducibility was less than 26%.The decision limits(CCα)and detection capabilities(CCβ)were obtained from a calibration curve and were in the ranges of 3.1-6.1μg/L and 4.0-7.4μg/L,respectively.The CCαand CCβvalues were below the recommended concentration,which was set at 10μg/L.The results show that the described method is suitable for the direct detection of TSs in bovine urine.This method can also be used to determine TSs in porcine urine.展开更多
The aim of this work was to develop a liquid chromatography-tandem mass spectrometry method for the determination of milk allergen and egg allergen in food products.Signature peptides GGLEPINFQTAADQAR,VGINYWLAHK,VLVLD...The aim of this work was to develop a liquid chromatography-tandem mass spectrometry method for the determination of milk allergen and egg allergen in food products.Signature peptides GGLEPINFQTAADQAR,VGINYWLAHK,VLVLDTDYK,FFVAPFPEVFGK,and NAVPITPTLNR were confirmed and synthesized as the quantitative peptide of ovalbumin,α-lactalbumin,β-lactoglobulin,α_(S1)-casein andα_(S2)-casein,the relative isotope-labeled internal standards were used in the quantitative analysis.Linear range was in the range of0.5-5000.0 nmol/L for egg and milk allergen in bread,cake,cookie,rice crust and wheat flour samples with free from egg and milk,the limits of detection of milk allergens and egg allergen were in the range between0.94 mg/100 g and 56.71 mg/100 g,limits of quantification of milk allergens and egg allergen were in the range between 2.36 mg/100 g and 141.78 mg/100 g.The recoveries ranged from 76.7%to 122.8%,the relative standard deviations were in the range of 1.60%-15.60%.The developed method has been successfully used for the detection of egg and milk allergen in various food samples.展开更多
建立QuEChERS-超高效液相色谱-串联质谱法测定土壤中戊唑醇、倍硫磷等农药残留,样品经乙腈振荡提取,加入盐包,振荡、离心,取上清液加入装有净化剂的15 m L萃取管中,振荡离心后取上清液过滤膜上机测定,质谱采用电喷雾电离、多反应检测模...建立QuEChERS-超高效液相色谱-串联质谱法测定土壤中戊唑醇、倍硫磷等农药残留,样品经乙腈振荡提取,加入盐包,振荡、离心,取上清液加入装有净化剂的15 m L萃取管中,振荡离心后取上清液过滤膜上机测定,质谱采用电喷雾电离、多反应检测模式(Multiple Reaction Monitoring,MRM)检测。检测结果显示,该方法线性良好,相关系数为0.992~0.999,在20、50、100μg·kg^(-1)3个水平浓度下加标回收率在80%~120%,相对标准偏差在20%以下。该方法简单、快捷、灵敏度高,满足检测要求。展开更多
目的:建立超高效液相色谱-串联质谱法测定动物源性食品中五氯酚的方法。方法:乙腈超声提取样品,离心取上清液氮吹至近干,使用甲醇和正己烷进行溶解,离心取下层液体经Agilent plus C_(18)色谱柱(50 mm×2.1 mm,1.8μm)分离,流动相为...目的:建立超高效液相色谱-串联质谱法测定动物源性食品中五氯酚的方法。方法:乙腈超声提取样品,离心取上清液氮吹至近干,使用甲醇和正己烷进行溶解,离心取下层液体经Agilent plus C_(18)色谱柱(50 mm×2.1 mm,1.8μm)分离,流动相为乙腈-乙酸铵水溶液(含0.1%甲酸),梯度洗脱,采用电喷雾电离,多反应监测模式下进行检测。结果:方法在0.50~20.00μg·L^(-1)具有良好的线性关系(r>0.9995),方法的检出限为0.50μg·kg^(-1),定量限为1.67μg·kg^(-1)。样品的回收率为81.0%~98.8%,相对标准偏差为0.54%~3.86%。结论:该方法符合《实验室质量控制规范食品理化检测》(GB/T 27404—2008)中的技术要求,适用于动物源性食品中五氯酚残留的测定。展开更多
目的 建立一测多评(quantitative analysis of multi-components by single marker, QAMS)法同时测定穿心莲中9种成分含量的分析方法。方法 采用超高效液相色谱-串联质谱法,以穿心莲内酯为内参物,建立该成分与连翘苷、齐墩果酸、咖啡酸...目的 建立一测多评(quantitative analysis of multi-components by single marker, QAMS)法同时测定穿心莲中9种成分含量的分析方法。方法 采用超高效液相色谱-串联质谱法,以穿心莲内酯为内参物,建立该成分与连翘苷、齐墩果酸、咖啡酸、穿心莲内酯、脱水穿心莲内酯、穿心莲新酯、去氧穿心莲内酯、脱水穿心莲内酯琥珀酸半酯、亚硫酸氢钠穿心莲内脂的相对校正因子,利用相对校正因子来计算各成分的含量,同时将QAMS法计算结果和外标法实测值进行比较。结果 相对校正因子重现性良好,使用QAMS法与外标法所测得的结果无明显的差异。结论 QAMS法适用于穿心莲中9种成分的同时测定,以保证质量的可靠性。展开更多
建立一种基于美国官方分析化学师协会(Association of Official Analytical Chemists,AOAC)方法检测黑果枸杞及其制品中花青素含量的改进pH示差法。考察了黑果枸杞及其制品中花青素的最佳提取和检测条件,通过液相色谱-三重四级杆串联质...建立一种基于美国官方分析化学师协会(Association of Official Analytical Chemists,AOAC)方法检测黑果枸杞及其制品中花青素含量的改进pH示差法。考察了黑果枸杞及其制品中花青素的最佳提取和检测条件,通过液相色谱-三重四级杆串联质谱法鉴别出黑果枸杞中花青素的具体化学结构,并计算出混合花青素的平均摩尔质量。通过分光光度法测得混合花青素的平均摩尔消光系数,对改进后的pH示差法进行方法学验证和花青素的含量测定。结果显示,最佳提取和检测条件如下:黑果枸杞花青素提取溶剂为盐酸-80%(体积分数)乙醇(3∶97,体积比),料液比为1∶100(g∶mL),提取温度为50℃,提取时间为30 min,缓冲溶液稀释5倍后静置平衡20 min。液相色谱-三重四级杆串联质谱法鉴别黑果枸杞中主要以矮牵牛素类花青素为主(占97.96%),黑果枸杞特有的混合花青素平均摩尔质量为912.7 g/mol,平均摩尔消光系数为29591 L/(mol·cm)。pH示差法改进后能够满足方法学验证要求,固体样品和液体样品最低检出限分别为28.2 mg/100 g、0.282 mg/100 mL。方法改进后花青素提取增长率均大于20%,静置平衡20 min后单次检测结果精密度小于0.3%。以矮牵牛素类花青素代替矢车菊素-3-O-葡萄糖苷计算花青素含量平均提高了2.41倍,能真实地反映黑果枸杞及其制品中花青素的含量。展开更多
基于食品基质中松仁过敏原Pin k 2建立了一种超高效液相色谱-串联质谱法。将松仁经过研磨、脱脂、浸提、酶解后经Easy-nLC 1000-QExactive高分辨质谱仪进行分离分析,结合Uniprot蛋白数据库以及ProteinPilotTM软件对质谱图进行数据处理,...基于食品基质中松仁过敏原Pin k 2建立了一种超高效液相色谱-串联质谱法。将松仁经过研磨、脱脂、浸提、酶解后经Easy-nLC 1000-QExactive高分辨质谱仪进行分离分析,结合Uniprot蛋白数据库以及ProteinPilotTM软件对质谱图进行数据处理,经BLAST验证特异性,最终筛选3条松仁特异性肽段。方法学验证结果表明,方法在0.001~50mg/mL范围内线性关系良好,定量限为1mg/kg;在饼干、巧克力和饮料3种空白基质中的平均回收率为88.50%~107.57%,相对标准偏差不高于6.08%,基质效应为89.77%~96.13%。该方法具有灵敏度高、特异性好的优势,可应用于饼干、巧克力、饮料等食品样品中松仁过敏原的检测,为我国食品标签真实性检验及食品中隐性过敏原的检测提供技术支持。展开更多
文摘The measurement of urine catecholamine and metanephrine concentrations is important for biochemical screening and diagnosis of pheochromocytoma.The goal of this work was to develop a simple liquid chromatography-tandem mass spectrometry(LC-MS/MS)method for determining catecholamines and metanephrines in urine to replace an existing liquid chromatographic method using electrochemical detection.Urine samples were prepared using Oasis weak-cation-exchange cartridges.The eluate was analyzed on an Agilent ZORBAX Eclipse Plus Phenyl-Hexyl column in 3 min.Adrenaline,noradrenaline,dopamine,metanephrine,normetanephrine,and their deuterated internal standards were monitored in positive electrospray ionization mode by multiple reaction monitoring(MRM).No evidence of ion suppression was observed.The assay was linear up to 5μmol/L for adrenaline,5μmol/L for noradrenaline,6.1μmol/L for dopamine,5.6μmol/L for metanephrine,and 34.6μmol/L for normetanephrine,with lower limits of quantification of 5,5,12,6 and 7nmol/L,respectively.The intra-day and inter-day precisions for all analytes ranged from 0.59%to 4.64%and1.98%to 4.80%,respectively.External quality assurance samples were assayed and showed excellent agreement with the target values.This simple method provides an improved assay for determining urine catecholamines and metanephrines.
基金National Key Research and Development Program of China(Project No.2018YFC1603400)Science and Technology Program of Hebei Province(Project No.19225503D)Technical Support Project of State Administration for Market Regulation(Project No.2019YJ009).
文摘In this experiment,a liquid chromatography tandem mass spectrometry method was built to determine 15 pesticide residues in Chinese cabbage and cucumber samples based on online turbulent flow chromatography purification.After modified quick,easy,cheap,effective,rugged,and safe(QuEChERS)extraction,extracts were directly injected to the TLX(TurboFlow Liquid Xcalibur)system and brought to TurboFlow™columns for on-line purification and then transferred to analytical column for further separation and analysis.TurboFlow™columns types,transfer flow rate,and transfer time were optimized.Limits of detection and limits of quantification of the method obtained for 15 pesticide residues were ranged between 0.2–1.0μg/kg and 0.5–2.0μg/kg in Chinese cabbage and cucumber samples.Recoveries of pesticide residues were in range of 75.3%–103.7%.Matrix effects for 15 pesticides were in range of 5.6%–106.6%.The developed method has been successfully used for the determination of 15 pesticide residues in real samples.
文摘Five thyreostats(TSs),namely tapazole,thiouracil,methylthiouracil,propylthiouracil,and phenylthiouracil,were determined in bovine urine using ultra-high performance liquid chromatography-tandem mass spectrometry(UHPLC-MS/MS)in positive electrospray ionization mode.Extraction and clean-up were achieved using a ChemElut cartridge with tert-butyl methyl ether,without a derivatization step.Separation was achieved on an Acquity UPLC SS T3 column.The mobile phase was acetonitrile and water containing 0.2%(v/v)formic acid.The mass spectrometer was operated in multiple reaction monitoring mode.Urine samples were spiked with TS solution at levels corresponding to 5,10,15,and 20μg/L.The accuracy(internal standard corrected)ranged from 92%to 107%,with a repeatability precision(relative standard deviation,RSD)less than 15%for all five analytes.The RSDs within-laboratory reproducibility was less than 26%.The decision limits(CCα)and detection capabilities(CCβ)were obtained from a calibration curve and were in the ranges of 3.1-6.1μg/L and 4.0-7.4μg/L,respectively.The CCαand CCβvalues were below the recommended concentration,which was set at 10μg/L.The results show that the described method is suitable for the direct detection of TSs in bovine urine.This method can also be used to determine TSs in porcine urine.
基金supported by National Key Research and Development Program of China(2019YFC1606400)Science and Technology Project of State Administration for Market Regulation(2021MK023)+1 种基金Hebei Province High-level Talent Funding Program(A201901008)Research Project of Hebei Administration for Market Regulation(2020ZD12)。
文摘The aim of this work was to develop a liquid chromatography-tandem mass spectrometry method for the determination of milk allergen and egg allergen in food products.Signature peptides GGLEPINFQTAADQAR,VGINYWLAHK,VLVLDTDYK,FFVAPFPEVFGK,and NAVPITPTLNR were confirmed and synthesized as the quantitative peptide of ovalbumin,α-lactalbumin,β-lactoglobulin,α_(S1)-casein andα_(S2)-casein,the relative isotope-labeled internal standards were used in the quantitative analysis.Linear range was in the range of0.5-5000.0 nmol/L for egg and milk allergen in bread,cake,cookie,rice crust and wheat flour samples with free from egg and milk,the limits of detection of milk allergens and egg allergen were in the range between0.94 mg/100 g and 56.71 mg/100 g,limits of quantification of milk allergens and egg allergen were in the range between 2.36 mg/100 g and 141.78 mg/100 g.The recoveries ranged from 76.7%to 122.8%,the relative standard deviations were in the range of 1.60%-15.60%.The developed method has been successfully used for the detection of egg and milk allergen in various food samples.
文摘建立QuEChERS-超高效液相色谱-串联质谱法测定土壤中戊唑醇、倍硫磷等农药残留,样品经乙腈振荡提取,加入盐包,振荡、离心,取上清液加入装有净化剂的15 m L萃取管中,振荡离心后取上清液过滤膜上机测定,质谱采用电喷雾电离、多反应检测模式(Multiple Reaction Monitoring,MRM)检测。检测结果显示,该方法线性良好,相关系数为0.992~0.999,在20、50、100μg·kg^(-1)3个水平浓度下加标回收率在80%~120%,相对标准偏差在20%以下。该方法简单、快捷、灵敏度高,满足检测要求。
文摘目的 建立一测多评(quantitative analysis of multi-components by single marker, QAMS)法同时测定穿心莲中9种成分含量的分析方法。方法 采用超高效液相色谱-串联质谱法,以穿心莲内酯为内参物,建立该成分与连翘苷、齐墩果酸、咖啡酸、穿心莲内酯、脱水穿心莲内酯、穿心莲新酯、去氧穿心莲内酯、脱水穿心莲内酯琥珀酸半酯、亚硫酸氢钠穿心莲内脂的相对校正因子,利用相对校正因子来计算各成分的含量,同时将QAMS法计算结果和外标法实测值进行比较。结果 相对校正因子重现性良好,使用QAMS法与外标法所测得的结果无明显的差异。结论 QAMS法适用于穿心莲中9种成分的同时测定,以保证质量的可靠性。
文摘基于食品基质中松仁过敏原Pin k 2建立了一种超高效液相色谱-串联质谱法。将松仁经过研磨、脱脂、浸提、酶解后经Easy-nLC 1000-QExactive高分辨质谱仪进行分离分析,结合Uniprot蛋白数据库以及ProteinPilotTM软件对质谱图进行数据处理,经BLAST验证特异性,最终筛选3条松仁特异性肽段。方法学验证结果表明,方法在0.001~50mg/mL范围内线性关系良好,定量限为1mg/kg;在饼干、巧克力和饮料3种空白基质中的平均回收率为88.50%~107.57%,相对标准偏差不高于6.08%,基质效应为89.77%~96.13%。该方法具有灵敏度高、特异性好的优势,可应用于饼干、巧克力、饮料等食品样品中松仁过敏原的检测,为我国食品标签真实性检验及食品中隐性过敏原的检测提供技术支持。
