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
Chinese herbal compound is playing an important role on curing human diseases.And it has been a trend that Chinese herbal compound is being used all over the world in 21 century.However,our Chinese herbal compound is ...Chinese herbal compound is playing an important role on curing human diseases.And it has been a trend that Chinese herbal compound is being used all over the world in 21 century.However,our Chinese herbal compound is facing serious challenge for the lack of canonical system of quality criterion for Chinese herbal compound so it has been a urgent problem to set up the quality control standards and reveal therapeutic basis of Chinese herbal compound.In order to give full play to the advantages of Chinese herbal compound,modern scientific and technological is used to research of Chinese herbal compound,especially the high performance liquid chromatography tandem mass spectrometry(HPLC-MS),because it is high sensitive,rapid,and obtain more information.It is very necessary that HPLC-MS is uesed to elucidate the effective components of basic substances of Chinese Herbal Compound,and endow traditional Chinese medicine with modern scientific connotation.展开更多
The method of reversed-phase high performance liquid chromatography was established for the determination of effective components in OC-CS spray using double wavelength UV detection.The method was utilized under follo...The method of reversed-phase high performance liquid chromatography was established for the determination of effective components in OC-CS spray using double wavelength UV detection.The method was utilized under following conditions:a column of Kromasil C18(250 mm × 4.6 mm,5 μm),mobile phase consisting of methanol/water(80 /20) at a flow rate of 0.8 mL/min,column temperature of 25 ℃,and the UV detection at 227 nm and 300 nm.Three key components in OC-CS spray could be distinguished clearly,including o-chlorobenzalmalononitrile(CS),oleoresin capsicum(OC) and dihydrocapsaicin(DC).This method has the advantages of fast,simple and satisfactory linear relationship between UV absorption and concentration.It may be considered to turn into a standard method for detection of related components in the spray.展开更多
Modification was made on the reversed-phase high performance liquid chromatography(RP-HPLC)with Yue et al's method as a base.The modified RP-HPLC was used to detect leukotriene B_4(LTB_4)and 5-hydroxyeicosatetraen...Modification was made on the reversed-phase high performance liquid chromatography(RP-HPLC)with Yue et al's method as a base.The modified RP-HPLC was used to detect leukotriene B_4(LTB_4)and 5-hydroxyeicosatetraenoic acid(5-HETE).It was found that the modified method has the merits of simpler procedures,shorter testing time and more satisfactory efficacy.展开更多
A high-performance liquid chromatography was describ-ed to measure the concentration of human 3-methylhistidine in urine witho-phthaldialdehyde pre-column derivatization.This assay system resultedin a clear separation...A high-performance liquid chromatography was describ-ed to measure the concentration of human 3-methylhistidine in urine witho-phthaldialdehyde pre-column derivatization.This assay system resultedin a clear separation of 3-methylhistidine derivative from other derivativ-es in urine within 25 min.Linearity,recovery and coefficients of vari-ation were studied.The method has been successfully applied to routineanalysis for clinical studies and diagnosis.展开更多
Modern porous monoliths have been conceived as a new class of stationary phases for high performance liquid chromatography(HPLC) in classical columns in the early 1990s and later extended to the capillary format.These...Modern porous monoliths have been conceived as a new class of stationary phases for high performance liquid chromatography(HPLC) in classical columns in the early 1990s and later extended to the capillary format.These monolithic materials are prepared using simple processes carried out in an external mold(inorganic monoliths) or within the confines of the column(organic monoliths and all capillary columns).These methods afford macroporous materials with large through-pores that enable applications in a rapid flow-through mode.Since all the mobile phase must flow through the monolith,the convection considerably accelerates mass transport within the monolithic separation medium and improves the separations.As a result,the monolithic columns perform well even at very high flow rates.The applications of monolithic capillary columns are demonstrated on numerous separations in the HPLC mode.展开更多
An HPLC method was established to control the quality of PolygonumavculareL. The active ingredients in PolygonumavculareL. samples were extracted with methanol, and then analyzed by high-performance liquid chromatogra...An HPLC method was established to control the quality of PolygonumavculareL. The active ingredients in PolygonumavculareL. samples were extracted with methanol, and then analyzed by high-performance liquid chromatography （HPLC）. The fingerprint of PolygonumavculareL. as well as its 11 typical peaks were established. The HPLC method demonstrated good precision, reproducibility, and stability, with the relative standard deviations of retention time and peak area less than 3%.展开更多
目的:建立一种超高效液相色谱串联质谱法(Ultra Performance Liquid Chromatography Tandem Mass Spectrometry,UPLC-MS)法测定保健食品中非法添加乌地那非、氯地那非含量的检测方法。方法:色谱柱为Agilent ZORBX Eclipse Plus C_(18)柱...目的:建立一种超高效液相色谱串联质谱法(Ultra Performance Liquid Chromatography Tandem Mass Spectrometry,UPLC-MS)法测定保健食品中非法添加乌地那非、氯地那非含量的检测方法。方法:色谱柱为Agilent ZORBX Eclipse Plus C_(18)柱(50 mm×2.1 mm,1.8μm),以0.1%甲酸水溶液-乙腈(65∶35)为流动相梯度洗脱,流速0.2 mL·min^(-1),柱温35℃;采用电喷雾离子源正模式多反应监测模式,外标法定量。结果:溶剂空白无干扰,乌地那非、氯地那非在10~200 ng·mL^(-1)时线性关系良好,相关系数分别为0.9990和0.9997;乌地那非的平均回收率为90.0%~104.3%,相对标准偏差为0.2%~3.8%;氯地那非的平均回收率为92.3%~105.8%,相对标准偏差为0.3%~2.2%;两者方法检出限、定量限分别为25μg·kg^(-1)和50μg·kg^(-1)。结论:建立的方法准确、灵敏、专属性强,适用于保健食品中非法添加乌地那非、氯地那非的痕量分析。展开更多
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.
文摘Chinese herbal compound is playing an important role on curing human diseases.And it has been a trend that Chinese herbal compound is being used all over the world in 21 century.However,our Chinese herbal compound is facing serious challenge for the lack of canonical system of quality criterion for Chinese herbal compound so it has been a urgent problem to set up the quality control standards and reveal therapeutic basis of Chinese herbal compound.In order to give full play to the advantages of Chinese herbal compound,modern scientific and technological is used to research of Chinese herbal compound,especially the high performance liquid chromatography tandem mass spectrometry(HPLC-MS),because it is high sensitive,rapid,and obtain more information.It is very necessary that HPLC-MS is uesed to elucidate the effective components of basic substances of Chinese Herbal Compound,and endow traditional Chinese medicine with modern scientific connotation.
基金Sponsored by the Basic Research Funds of Beijing Institute of Technology (20081642007)
文摘The method of reversed-phase high performance liquid chromatography was established for the determination of effective components in OC-CS spray using double wavelength UV detection.The method was utilized under following conditions:a column of Kromasil C18(250 mm × 4.6 mm,5 μm),mobile phase consisting of methanol/water(80 /20) at a flow rate of 0.8 mL/min,column temperature of 25 ℃,and the UV detection at 227 nm and 300 nm.Three key components in OC-CS spray could be distinguished clearly,including o-chlorobenzalmalononitrile(CS),oleoresin capsicum(OC) and dihydrocapsaicin(DC).This method has the advantages of fast,simple and satisfactory linear relationship between UV absorption and concentration.It may be considered to turn into a standard method for detection of related components in the spray.
文摘Modification was made on the reversed-phase high performance liquid chromatography(RP-HPLC)with Yue et al's method as a base.The modified RP-HPLC was used to detect leukotriene B_4(LTB_4)and 5-hydroxyeicosatetraenoic acid(5-HETE).It was found that the modified method has the merits of simpler procedures,shorter testing time and more satisfactory efficacy.
文摘A high-performance liquid chromatography was describ-ed to measure the concentration of human 3-methylhistidine in urine witho-phthaldialdehyde pre-column derivatization.This assay system resultedin a clear separation of 3-methylhistidine derivative from other derivativ-es in urine within 25 min.Linearity,recovery and coefficients of vari-ation were studied.The method has been successfully applied to routineanalysis for clinical studies and diagnosis.
基金Supported by grants of the National Institute of General Medical Sciences,National Institutes of Health(GM-48364),and the Materials Sciences and Engineering Division of the U.S.Department of Energy(DE-AC02-05CH11231).
文摘Modern porous monoliths have been conceived as a new class of stationary phases for high performance liquid chromatography(HPLC) in classical columns in the early 1990s and later extended to the capillary format.These monolithic materials are prepared using simple processes carried out in an external mold(inorganic monoliths) or within the confines of the column(organic monoliths and all capillary columns).These methods afford macroporous materials with large through-pores that enable applications in a rapid flow-through mode.Since all the mobile phase must flow through the monolith,the convection considerably accelerates mass transport within the monolithic separation medium and improves the separations.As a result,the monolithic columns perform well even at very high flow rates.The applications of monolithic capillary columns are demonstrated on numerous separations in the HPLC mode.
文摘An HPLC method was established to control the quality of PolygonumavculareL. The active ingredients in PolygonumavculareL. samples were extracted with methanol, and then analyzed by high-performance liquid chromatography （HPLC）. The fingerprint of PolygonumavculareL. as well as its 11 typical peaks were established. The HPLC method demonstrated good precision, reproducibility, and stability, with the relative standard deviations of retention time and peak area less than 3%.
文摘目的:建立一种超高效液相色谱串联质谱法(Ultra Performance Liquid Chromatography Tandem Mass Spectrometry,UPLC-MS)法测定保健食品中非法添加乌地那非、氯地那非含量的检测方法。方法:色谱柱为Agilent ZORBX Eclipse Plus C_(18)柱(50 mm×2.1 mm,1.8μm),以0.1%甲酸水溶液-乙腈(65∶35)为流动相梯度洗脱,流速0.2 mL·min^(-1),柱温35℃;采用电喷雾离子源正模式多反应监测模式,外标法定量。结果:溶剂空白无干扰,乌地那非、氯地那非在10~200 ng·mL^(-1)时线性关系良好,相关系数分别为0.9990和0.9997;乌地那非的平均回收率为90.0%~104.3%,相对标准偏差为0.2%~3.8%;氯地那非的平均回收率为92.3%~105.8%,相对标准偏差为0.3%~2.2%;两者方法检出限、定量限分别为25μg·kg^(-1)和50μg·kg^(-1)。结论:建立的方法准确、灵敏、专属性强,适用于保健食品中非法添加乌地那非、氯地那非的痕量分析。
