Determination of thyreostats in bovine urine using ultra-high performance liquid chromatography-tandem mass spectrometry

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.

An Ultra-High Performance Liquid Chromatography-Tandem Mass Spectrometry Method for the Quantification of Vancomycin Requiring Only 2 μL of Rabbit Serum

A highly sensitive ultra-high performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) method was developed for the quantification of vancomycin (VAN) in low volumes of rabbit serum. For each analysis, 2 μL rabbit serum was precipitated with methanol that contained the internal standard teicoplanin (TEI). The supernatant was transferred into a 384 well-plate, diluted with water, covered with a pierceable silicone mat and 5 μL was analyzed in positive ionization mode. The UHPLC-MS/MS consisted of an Agilent 1290 Infinity UHPLC system connected to an AB Sciex QTrap®5500 hybrid linear ion-trap triple quadrupole mass spectrometer equipped with a Turbo Spray source. Chromatographic separation was achieved using a Waters Acquity UPLC BEH C18 (1.7 μm, 2.1 mm × 100 mm) column, a VanGuard (1.7 μm, 2.1 × 5 mm) guard column and a mobile phase of water and methanol both containing 5 mM ammonium acetate with 0.1% formic acid. VAN was quantified with multiple reaction monitoring using the transitions of m/z 725.5/144.2, and TEI was monitored at m/z 940.6/316.4. The accuracy, precision, linearity, range and lower limit of quantification (LLOQ) were determined. The accuracy was ≤9.93% and the precision was ≤10.6%. The range was established as 0.1 to 40 μg·mL-1. The LLOQ was 0.1 μg·mL-1 VAN requiring 2 μL of sample with an accuracy of -20.2% and precision of 8.39%. The method was applied successfully to determine the VAN concentrations in rabbit serum after the i.v. administration of VAN via implanted ear catheters.

Dimension-Enhanced Ultra-High Performance Liquid Chromatography/Ion Mobility-Quadrupole Time-of-Flight Mass Spectrometry Combined with Intelligent Peak Annotation for the Rapid Characterization of the Multiple Components from Seeds of Descurainia sophia

The complex composition of herbal metabolites necessitates the development of powerful analytical techniques aimed to identify the bioactive components.The seeds of Descurainia sophia(SDS)are utilized in China as a cough and asthma relieving agent.Herein,a dimension-enhanced integral approach,by combining ultra-high performance liquid chromatography/ion mobility-quadrupole time-of-flight mass spectrometry(UHPLC/IMQTOF-MS)and intelligent peak annotation,was developed to rapidly characterize the multicomponents from SDS.Good chromatographic separation was achieved within 38 min on a UPLC CSH C18(2.1×100 mm,1.7μm)column which was eluted by 0.1%formic acid in water(water phase)and acetonitrile(organic phase).Collision-induced dissociation-MS^(2)data were acquired by the data-independent high-definition MS^(E)(HDMS^(E))in both the negative and positive electrospray ionization modes.A major components knockout strategy was applied to improve the characterization of those minor ingredients by enhancing the injection volume.Moreover,a self-built chemistry library was established,which could be matched by the UNIFI software enabling automatic peak annotation of the obtained HDMS^(E)data.As a result of applying the intelligent peak annotation workflows and further confirmation process,a total of 53 compounds were identified or tentatively characterized from the SDS,including 29 flavonoids,one uridine derivative,four glucosides,one lignin,one phenolic compound,and 17 others.Notably,four-dimensional information related to the structure(e.g.,retention time,collision cross section,MS^(1)and MS^(2)data)was obtained for each component by the developed integral approach,and the results would greatly benefit the quality control of SDS.

Rapid Quantitative Determination of Isoprene Monomer in Living Taraxacum kok-saghyz by Ultra-High Performance Liquid Chromatography Tandem Mass Spectrometry

Taraxacum kok-saghyz(TKS)is rich in natural rubber(NR),a natural organic macromolecular compound composed of cis-1,4-polyisoprene,and may become the second NR-bearing plant for biochemical engineering development.In this paper,a rapid and quantitative ultra-high performance liquid chromatography tandem mass spectrometry(UHPLCMS/MS)method was established for determination of macromolecular biosynthesis substrate(dimethylallyl pyrophosphate,DMAPP)and initiator(farnesyl pyrophosphate,FPP)contained in TKS.A Kromasil C18 chromatographic column was used for separation,and the multi-reaction monitoring mode(MRM)of triple quadrupole mass spectrometry was used for detection.Quantification was performed by external calibration method.The results showed that the limit of detection(LOD)and the limit of quantitation(LOQ)of DMAPP were 2.42μg/L and 7.26μg/L,respectively,and the LOQ and the LOD of FPP were 1.02μg/L and 3.05μg/L,respectively.At a concentration of 1—1000μg/L,both analytes had good determination coefficients(>0.999)of calibration curve.The recoveries of DMAPP and FPP were between 99.0%and 117.1%.In real samples detection,the contents of DMAPP and FPP in TKS samples were between 23.32—82.77μg/L and 12.03—85.67μg/L,respectively.Thus,this approach is a reliable method to quantify DMAPP and FPP in TKS.

Simultaneous Determination of Ultraviolet Absorbers and Antibacterial Agents in Textiles by Ultra-High Performance Liquid Chromatography/Orbitrap High Resolution Mass Spectrometry

This paper reported a new analytical method for the simultaneous determination of seven benzotriazole ultraviolet absorbers and seven antibacterial agents in textiles. After ultrasonic extraction for the textile samples in methanol, the solutions were analyzed by ultra-high performance liquid chromotagraphy/orbitrap high resolution mass spectrometry (UPLC/Orbitrap HRMS). It showed that a good chromatographic separation for these target compounds was achieved by a Hypersil GOLD column (100 mm × 2.1 mm × 1.9 μm) with a gradient elution of methanol and 0.1% aqueous formic acid solution (containing 0.5 mmol/L ammonium acetate). Triclosan and 4-chloro-3,5-dimethyl phenol (PCMX) were detected by the orbitrap HRMS in an electrospray ionization (ESI) negative mode while the other twelve target compounds were detected by orbitrap HRMS in ESI positive mode. Full scan experiment was performed over the range from m/z 100 to m/z 500. These target compounds were routinely detected with mass accuracy below 2 × 10-6 (2 ppm) at the optimized conditions. The results showed that the limits of detection (LODs) were in the range from 0.1 to 0.3 μg/kg. The blank samples were spiked at three levels and their average recoveries varied from 80.5% to 96.3% while the relative standard deviation (RSD) changed from 3.2% to 9.9%. The present method was also applied for the determination of those ultraviolet absorbers and antibacterial agents in the commercial textiles.

Determination of 19 polyphenolic compounds in tea by ultra-high performance liquid chromatography combined with quadrupole-time of flight mass spectrometry

A rapid method was presented for the determination of 19 polyphenols in tea by ultra-high performance liquid chromatography coupled with quadrupole-time of flight mass spectrometry(UPLC-Q-TOF MS).Tea samples were extracted by 50%(V/V)ethanol,then separated by Waters Acquity BEH C18 column using a binary solvent system composed of acetonitrile and water(0.1%formic acid)by gradient elution.The analytes were determined by Q-TOF MS in TOF MS and information dependent acquisition(IDA)-MS/MS mode.The results showed that mass accuracy error of the 19 polyphenols were lower than 5.0×10^(-6),good linear relationship was got in range of 0.2–500μg/L and correlation coefficient was higher than 0.9990.The LOD was in the range of 0.002–0.100 mg/kg and the LOQ was in the range of 0.004–0.200 mg/kg.Recovery of the method was in range of 78.4%–109.2%with spike levels of 0.004–2.000 mg/kg,relative standard deviations were lower than 10%.The method was simple,rapid and accurate.It could be used for the rapid screening and quantitative analysis of 19 polyphenols in tea.

Determination of Sodium Pentachlorophenoxide Residues in Animal-derived Foods by Ultra-performance Liquid Chromatography-Tandem Mass Spectrometry (UPLC-MS/MS)

[Objectives]This study was conducted to establish an ultra-high performance liquid chromatography-tandem mass spectrometry for the rapid extraction of sodium pentachlorophenoxide from animal-derived food.[Methods]The samples were extracted with an acetonitrile water solution(8∶2),0.1 mol/L hydrochloric acid and a purification extraction bag with shaking.Centrifugation was performed to obtain supernatants,which were added to purification tubes containing PSA and C_(18) for purification,and then filtered with membranes for determination.Each test solution was separated by a ZORBAX Eclipse plus C_(18) column with acetonitrile and 5 mmol/L ammonium acetate as mobile phases,and determined with electrospray ionization and multiple reaction monitoring.[Results]The method had good linearity in the concentration range of 1.0-50 ng/ml,and the correlation coefficient was 0.9997.The limit of detection was 0.25μg/kg and the limit of quantification was 0.75μg/kg.The recovery was between 87.4%and 112.5%,and the RSD%was between 0.5%and 10.0%.[Conclusions]The method has simple operation and high sensitivity,and is suitable for trace detection of sodium pentachlorophenoxide in large quantities of animal-derived food.

Comparison of pharmacokinetics of different oral Panax notoginseng saponins using ultra-high performance liquid mass spectrometry

Objective:To discuss and compare the plasma pharmacokinetics after three oral Panax notoginseng saponin(PNS)administrations in beagle dogs.PNS is the main active ingredient of the traditional Chinese medicine(TCM)Panax notoginseng.Although its outstanding therapeutic efficacy has been demonstrated by various researchers,its broader application is restricted by the low bioavailability of PNS.Methods:An ultra-high performance liquid chromatographyetandem mass spectrometry(UPLC-MS/MS)method for the simultaneous quantification of notoginsenoside R1,ginsenoside Rg1,ginsenoside Rb1,ginsenoside Rd,and ginsenoside Re in beagle dog plasma was developed and validated.The plasma samples were subjected to liquideliquid extraction with acetone and methanol,and separated on an ACQUITY C18 column(100×2.1 mm ID,1.7 mm)using acetonitrile and water as the mobile phase with a run time of 4.5 min.Results:The analytes were detected without interference in Selected Reaction Monitoring mode with positive electrospray ionization.The validated method was successfully used in comparative pharmacokinetic studies of the five saponins in beagle dogs after oral administration of three PNS preparations.Blood samples were collected up to 192 h after administration and pharmacokinetic parameters were calculated using DAS 3.20 and SPSS 17.0.The AUC_(0-t)values of Re and R1 were significantly higher in soft capsules than in hard capsules.However,the AUC_(0-t)values between hard and soft capsules were not significantly different for the other three componentsdRb1,Rd and Rg1.Conclusion:Our intuitive analysis suggests that the bioavailability of PNS in soft capsules is greater than in hard capsules.

Determination of Ten Kinds of Alpha-2 Agonists Residues in Animal Derived Food by UHPLC-Triple Quadrupole/Composite Linear Ion Trap Mass Spectrometry

[Objectives]The paper was to establish an ultra high performance liquid chromatography-quadrupole/linear ion trap complex mass spectrometry for the determination of 10 kinds ofα2-receptor agonists in animal derived food.[Methods]The samples were extracted with sodium carbonate buffer solution and ethyl acetate,and analyzed by mass spectrometry after solid phase extraction and high performance liquid chromatography separation.[Results]Ten kinds ofα2-receptor agonists showed a good linear relationship in the range of 1-100μg/mL,with the average recovery of over 69%and the relative standard deviation less than 8.32%.The detection limit of 10 kinds of α_(2)-receptor agonists was up to 1μg/kg.[Conclusions]The method has good selectivity and strong anti-interference ability,and can meet the requirements of 10 kinds ofα2-receptor agonists residues in animal derived food.

超高效液相色谱-四极杆静电场轨道阱质谱法快速筛查测定抗疲劳类保健食品中112种化学药

建立了一种超高效液相色谱-四极杆静电场轨道阱质谱法(UPLC-Q-Orbitrap HRMS)快速筛查测定抗疲劳保健中112种非法添加化学药物的方法。收集了现有补充检验方法规定的90种以及实际工作中发现的化学药共112种,利用Q-Orbitrap HRMS和Trace Finder软件采集并记录每种药物的信息,建立高分辨质谱数据库。样品采用90%甲醇(含0.1%甲酸)超声萃取,加热电喷雾电离源(H-ESI)、正离子扫描方式采集数据。通过数据库筛查和鉴定非法添加化学成分。分别对样品前处理、色谱、质谱条件进行优化,并考察了每种物质的检出限、定量下限、线性范围。结果表明,112种化合物的检出限为0.0125~0.0625 mg/kg,定量下限为0.025~0.125 mg/kg,相关系数(r^(2))均不低0.999,方法的线性关系良好,回收率为62.0%~124%,相对标准偏差(RSD)为2.4%~8.9%。方法可用于保健食品中非法添加化学药物的高通量快速筛查。利用全扫描结果,还能发现数据库以外的可疑化合物,鉴定新的非法添加物。方法已用于实际工作,适用于抗疲劳类保健食品及普通食品中非法添加化学药的快速筛查。

Analysis of Pharmacodynamic Substance Basis of Fufang Changtai in Treating Colorectal Cancer by UPLC-Q-TOF-MS Combined with Network Pharmacology

[Objectives] To systematically study the main active components of Fufang Changtai(FFCT) in the treatment of colorectal cancer(CRC), and to explore its mechanism of action. [Methods] The main chemical components of FFCT were analyzed by ultra-high performance liquid chromatography with quadrupole time-of-flight mass spectrometry(UPLC-Q-TOF-MS) combined with automatic analysis platform, and the main pharmacodynamic substances of FFCT were studied by network pharmacology method and its mechanism of action was explored. The binding degree between the active components and the core targets were verified by molecular docking technology. [Results] A total of 86 compounds were identified from FFCT, among which 26 compounds were Ginsenoside Rg3, Ginsenoside Rb1, Astragaloside III, etc. The key target pathway enrichment analysis showed that FFCT played its role in the treatment of CRC mainly through the PI3K-Akt signaling pathway and MAPK signaling pathway. [Conclusions] This study comprehensively identified the FFCT components. Supplemented by network pharmacology and molecular docking technology, it is expected to provide a scientific theoretical basis and an important reference for FFCT therapeutic components identification, key target verification and mechanism of action in the treatment of CRC.

正相HPLC-MS/MS法测定人体血浆中西酞普兰对映异构体浓度

建立了正相高效液相色谱-串联质谱（HPLC-MS／MS）法测定人体血浆中西酞普兰（citalopram，CIT）对映异构体浓度。采用CHIRALCEL OJ—H（250mm×4．6mm×5μm）手性柱，利多卡因作为内标，流动相为y（正己烷）：y（无水乙醇）：V（Z乙胺）-70：30：0．1的溶液，流速为o．5mL·min^-1。血浆样品在碱性条件下用y（正己烷）：V（异丙醇）=98：2的溶液提取浓集后，选择大气压化学电离源和多反应离子监测（MRM）模式进行测定。CIT和内标检测离子对分别为m／z325．1→108．9和m／z235．4→86．1。rac—CIT的线性范围为0．156～50μg·L^-1，S-CIT的线性范围为0．078～25pg·L^-1，标准曲线的线性良好（r〉0．99）。rac—CIT、S—CIT和R—CIT的方法回收率分别为99．7％～101．5％，99．1％～103．3％，99．9％～100．2％；萃取回收率分别为73．5oA～75．1％，73．9％～76．0％，73．1％～74．3％。各组分的日内RSD和日间RSD均小于5．0％。

血液中氨基酸含量的高效液相色谱及其质谱联用测定方法研究进展

综述液相色谱法和液相色谱-质谱联用法测定血液中氨基酸含量的研究进展,评述了每种分析方法的特点和适用范围,为临床诊断相关代谢疾病提供辅助依据。

番茄酱中单氰胺检测衍生化条件的研究

建立了柱前衍生化高效液相色谱串联质谱法检测番茄酱中单氰胺的最佳衍生化条件;在衍生化试剂丹磺酰氯浓度为10mg/mL,反应温度为60℃,反应时间为1h,缓冲体系的pH值为10.5时,衍生效果最佳,单氰胺最低检测浓度为0.00005mg/kg,衍生产物在48h内稳定。

Integrated metabolomic profiling for analysis of antilipidemic effects of Polygonatum kingianum extract on dyslipidemia in rats

AIM To identify the effects and mechanism of action of Polygonatum kingianum(P. kingianum) on dyslipidemia in rats using an integrated untargeted metabolomic method.METHODS A rat model of dyslipidemia was induced with a high-fat diet(HFD) and rats were given P. kingianum [4 g/(kg·d)] intragastrically for 14 wk. Changes in serum and hepatic lipid parameters were evaluated. Metabolites in serum, urine and liver samples were profiled using ultra-highperformance liquid chromatography/mass spectrometry followed by multivariate statistical analysis to identify potential biomarkers and metabolic pathways.RESULTS P. kingianum significantly inhibited the HFD-induced increase in total cholesterol and triglyceride in the liver and serum. P. kingianum also significantly regulated metabolites in the analyzed samples toward normal status. Nineteen, twenty-four and thirty-eight potential biomarkers were identified in serum, urine and liver samples, respectively. These biomarkers involved biosynthesis of phenylalanine, tyrosine, tryptophan, valine, leucine and isoleucine, along with metabolism of tryptophan, tyrosine, phenylalanine, starch, sucrose, glycerophospholipid, arachidonic acid, linoleic acid, nicotinate, nicotinamide and sphingolipid.CONCLUSION P. kingianum alleviates HFD-induced dyslipidemia by regulating many endogenous metabolites in serum, urine and liver samples. Collectively, our findings suggest that P. kingianum may be a promising lipid regulator to treat dyslipidemia and associated diseases.

Mitochondrial metabolomic profiling for elucidating the alleviating potential of Polygonatum kingianum against high-fat diet-induced nonalcoholic fatty liver disease

BACKGROUND Developing mitochondrial regulators/nutrients from natural products to remedy mitochondrial dysfunction represent attractive strategies for therapy of nonalcoholic fatty liver disease(NAFLD).Polygonatum kingianum(PK)has been traditionally used in China as a medicinal and nutritional ingredient for centuries and can alleviate high-fat diet(HFD)-induced NAFLD by promoting mitochondrial functions.To date,the underlying molecular mechanism of PK for treating mitochondrial dysfunctions and thus alleviating NAFLD remains unclear.AIM To identify the molecular mechanism behind the mitochondrial regulatory action of PK against HFD-induced NAFLD in rats.METHODS NAFLD model was induced in rats with HFD.The rats were intragastrically administered PK(4 g/kg per day)for 14 wk.Metabolites in hepatic mitochondrial samples were profiled through ultra-high performance liquid chromatography/mass spectrometry followed by multivariate statistical analysis to find the potential biomarkers and metabolic pathways.RESULTS PK significantly restored the metabolites’levels in the mitochondrial samples.Ten potential biomarkers were identified in the analyzed samples.These biomarkers are involved in riboflavin metabolism.CONCLUSION PK can alleviate HFD-induced NAFLD by regulating the riboflavin metabolism and further improving the mitochondrial functions.Thus,PK is a promising mitochondrial regulator/nutrient for alleviating NAFLD-associated diseases.

UPLC-MS/MS法同时测定食品接触用油墨中20种光引发剂的迁移量

为评估食品接触用油墨中光引发剂的迁移风险,采用超高效液相色谱-串联质谱(UPLC-MS/MS)建立了同时测定食品接触用油墨中20种光引发剂迁移量的方法。以0.1%(体积分数)甲酸和甲醇为流动相进行梯度洗脱,采用多反应监测模式对目标物的定量离子和定性离子进行监测,检测迁移实验后食品模拟物中的20种光引发剂。结果表明,该方法对20种光引发剂的色谱分离效果良好,各物质在0.02~0.5 mg/L质量浓度范围内线性关系良好,检出限为0.01 mg/kg,定量下限为0.02 mg/kg。加标回收率为87.1%~104%,相对标准偏差(RSD)为2.1%~8.6%,在10款样品中共检出4类光引发剂。该方法简单、灵敏、准确,适用于食品接触用油墨中20种光引发剂迁移量的检测。

超高效液相色谱-四极杆飞行时间质谱法同时测定食品接触用塑料中50种添加剂的迁移量

为评估食品接触用塑料中添加剂的迁移风险,采用超高效液相色谱-四极杆飞行时间质谱(UPLCQTOF MS)建立了同时测定食品接触用塑料中50种添加剂迁移量的方法。以甲醇和0.01%(体积分数)甲酸-5 mmol/L乙酸铵溶液为流动相进行洗脱,采用目标离子采集(Target MS/MS)模式对目标物的一级离子与二级离子进行监测。结果表明,各物质在0.02~5 mg/L质量浓度范围内线性关系良好,方法检出限为0.01~0.1 mg/kg,加标回收率为92.6%~104%,相对标准偏差(RSD)为0.60%~8.4%。在20款实际样品中有12个样品检出塑料添加剂,其中2个样品检出壬基酚,迁移量为0.033~0.071 mg/kg;6个样品检出抗氧化剂1076和抗氧化剂168,迁移量为0.12~3.3 mg/kg;4个样品检出光引发剂369、光引发剂ITX和光引发剂TPO,迁移量为0.054~4.0 mg/kg。该方法简单、灵敏、准确,适用于食品接触用塑料中50种添加剂迁移量的检测。

UPLC-QTOF-MS Analysis on Isoflavones in Douchi

Douchi is a kind of traditional Chinese fermented soybean food.Ultra-high performance liquid chromatography quadrupole-time of flight mass spectrometry(UPLC-QTOF-MS)was applied to separate and identify 12 kinds of isoflavones in Douchi within 16 min.The chromatographic separation was carried out on an ACQUITY UPLC HSS T3 column with a gradient elution program where water containing 0.1%formic acid and acetonitrile containing 0.1%formic acid were used as mobile phases.Detection by using electrospray ionization of positive ion mode was applied in the mass spectrometry.Isoflavones were identified by determining the accurate mass and referring to references in this study.

食品加工机械材料橡胶密封垫圈中5种荧光增白剂迁移量的测定及其迁移规律研究

建立了一种高效液相色谱-串联质谱同时测定食品加工机械材料橡胶密封垫圈中5种荧光增白剂(FWA184、FWA185、FWA393、FWA367、FWA135)在不同食品模拟物中迁移量的检测方法。研究了食品加工机械材料橡胶密封垫圈中5种荧光增白剂在水、4%乙酸水溶液、50%乙醇水溶液和橄榄油4种食品模拟物中的迁移规律。实验结果表明,5种荧光增白剂在5~100μg/L范围内线性良好,相关系数r≥0.9991,方法定量下限为0.001~0.050 mg/kg。在橄榄油基质中,加标水平为0.05、0.1、0.5 mg/kg时,回收率为81.8%~101%,相对标准偏差为1.2%~5.6%(n=10)。方法快速简便,灵敏度、回收率和准确性能够满足食品接触材料及制品中荧光增白剂迁移量的测定要求。考察了食品模拟物种类、迁移温度、迁移时间对迁移量的影响。结果表明,在相同条件下,橡胶密封垫圈中5种荧光增白剂在橄榄油模拟物中迁移量最高;当温度升高时迁移量显著增加;随着时间的延长,迁移量呈现由快速迁移至缓慢迁移,随后趋于平衡的过程。