Determination of Tetracyclines and Their Epimers in Agricultural Soil Fertilized with Swine Manure by Ultra-High-Performance Liquid Chromatography Tandem Mass Spectrometry

A rapid, sensitive and specific ultra-high-performance liquid chromatography tandem mass spectrometry （UPLC-MS） method was developed for the analysis of tetracycline antibiotics, including tetracycline （TC）, oxytetracycline （OTC）, chlortetracycline （CTC） and their 4-epimers （4-epiTCs） in agricultural soil fertilized with swine manure. Soil samples were extracted and cleaned-up with 10 mL EDTA-McIlvaine buffer solution （pH 4.0）, then cleaned-up and pre-concentrated using the Oasis MAX cartridge and then eluted with 1 mL solution by mixing formic acid, methanol and water at a ratio of 2：15：83 （v/v/v）. The purified samples were separated by an ACQUITY UPLC BEH C18 column using acetonitrile and water containing 0.1% formic acid mobile phase and detected by a single quadrupole MS. The limits of detection for the soil extraction method （LODsoil） ranged from 0.6-2.5 lag kg-~ with recoveries from 23.3-159.2%. Finally, the method was applied to an agricultural field in an area with intensive pig-fattening farming. Tetracyclines were detected in soil from 2.8 to 42.4 μg kg-1 soil. These results demonstrate that soil from swine farms can become severely contaminated with tetracycline antibiotics and their metabolites.

Determination of Steroid Hormone Residues in Fish Tissues Using Gel Permeation Chromatography and Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry

A highly sensitive method was developed for the simultaneous determination of 8 steroid hormones in high-fat fish tissues using ultra high performance liquid chromatography-tandem mass spectrometry(UPLC-MS/MS).The 8 steroid hormones were extracted from the tissues with diethyl ether.Differing from other common purification methods,the extract solutions were cleaned by gel permeation chromatography(GPC) using ethyl acetate-cyclohexane solution(1:1,v/v) as the mobile phase.The separation of target compounds was carried out by a BEH C18 column and a gradient elution consisting of acetonitrile and 0.2% aqueous formic acid(v/v).The compounds were detected under the multiple reaction monitoring(MRM) mode and quantified with external standard method.This method was validated with respect to linearity,specificity,accuracy and precision.A linearity with correlation coefficient larger than 0.995 was achieved in the range of 0.5 to 50 ng m L^(-1).The average recoveries at the spiked levels of 1.0,5.0,and 10.0 μg kg^(–1) varied between 81.7% and 90.8%,with the relative standard deviations(n=5) ranged from 3.50% to 10.0%.The limit of quantification(LOQ) for 8 steroid hormones ranged from 0.2 to 1.5 μg kg^(-1).It was concluded that this method can be successfully applied for the determination of 8 steroid hormones in complicated matrices including high-fat fish tissues.

Simultaneous Determination of Bisphenols and Alkylphenols in Water by Solid Phase Extraction and Ultra Performance Liquid Chromatography-tandem Mass Spectrometry

To establish an analytical method for determination of four bisphenols （BPA, BPB, BPF, and BPS） and two alkylphenols （4-n-OP, 4-n-NP） in water by ultra performance liquid chromatography- tandem mass spectrometry （UPLC/MS/MS）. The water samples were extracted and condensed with solid-phase extraction （SPE） using C18 cartridges and eluted by acetonitrile. Separation was carried out with Acquity BEH C8 column and detection were performed by UPLC/MS/MS. Quantification was calculated by using the internal standard BPA-d16 and 4-n-NP-d8. The linear correlation coefficients of these compounds in the range of 1.0-100.0μg/L were all over 0.999. The minimum detectable concentrations were 0.75-1.0 ng/L, and the recoveries ranged from 87.0% to 106.9%.

Uncertainty Evaluation of Determination of Microcystin MC-LR in Environmental Samples by Solid Phase Extraction-Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry

To assess uncertainty of determination of MC-LR in environmental samples by solid phase extraction- ultra performance liquid chromatography- tandem mass spectrometry,the sources of the uncertainty were evaluated firstly,and the expanded uncertainty was calculated finally.The results show that when MC-LR concentration in the water samples was 0.50 μg/L,the expanded uncertainty was 0.00628 μg/L(k=2).

A Rapid Separation and Highly Determination of Paraben Species by Ultra-Performance Liquid Chromatography —Electrochemical Detection

In this study, a new technique was developed using rapid ultra-performance liquid chromatography (UPLC)-based separation coupled with electrochemical detection by a boron-doped diamond (BDD) electrode for the detection and quantification of three commonly used parabens (methylparaben (MP), ethylparaben (EP) and propylparaben (PP)). We aimed to reduce the analysis time by using UPLC coupled with a short reverse phase C 18 monolithic column (25 mm×4.6 mm). Operating the monolithic column at low back-pressure resulted in high flow rates. A mobile phaseconsisting of a 25:75 (v/v) ratio of acetonitrile:0.05 Mphosphate buffer (pH 5) at a flow rate of 2.5 mL·min?1 was used to perform the separation. The amperometric detection with the BDD electrode was found to be optimal and reliably reproducible at a detection potential of 1.5 V vs. Ag/AgCl. Under these conditions, the separation of the three targetanalytes (MP, EP and PP) was achieved in 2 min and was linear within a sample concentration range of 0.1 to 50.0 mg·L?1 (r2 values of 0.9970, 0.9994 and 0.9994 for MP, EP and PP, respectively). This method was successfully applied to determine the concentrations of each parabeninsix real samples with therecoveries ranging from of 80.3% - 98.9% for all three parabensfrom samples spiked at 12, 22 and 32 mg·L?1. Therefore, the proposed method can be used as an alternative rapid and selective method for the determination of paraben levels in real samples.

Chemical Components of Achyranthes bidentata Leaves by Ultra High Performance Liquid Chromatography-Mass Spectrometry

[Objectives] To study the chemical components and relative content of Achyranthes bidentata leaves and provide a scientific basis for further development and utilization of A. bidentata leaves.[Methods] The chemical components of A. bidentata leaves were rapidly analyzed using the ultra high performance liquid chromatography-time of flight-high resolution mass spectrometry (UHPLC-TOF-MS).[Results] Thirty eight chemical compounds were identified in samples of A. bidentata leaves collected from Wen County of Henan Province, in which seven chemical compounds had the relative content higher than 5%, linoleic acid reached 25.7% and inokosterone A reached 13.8%.[Conclusions] A. bidentata leaves contain many kinds of chemical compounds. This study is expected to provide a certain basis for further extraction of linoleic acid and inokosterone A.

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.

Development of a Fast and Facile Analytical Approach to Quantify Radiometabolites in Human Plasma Samples Using Ultra High Performance Liquid Chromatography

Introduction: Conventional metabolite analyses often require manual sample preparation, generating variability of measurements. This study describes a new method to quantify radiometabolites in blood, combining ultra high performance liquid chromatography (UHPLC) and turbulent flow chromatography, an alternative fully automated process allowing analyte’s extraction. Methods: A new radiotracer for dopamine transporter imaging, namely LBT-999, was used to demonstrate the method’s robustness. Matrix effect, Turboflow column loading, linearity, specificity and precision were evaluated with in vitro samples of LBT-999 in human plasma. Radiodetector sensitivity and preliminary evaluation were respectively determined by analysis of calibrated samples of [18F]LBT-999 and blood samples from 4 healthy subjects injected with [18F]LBT-999, withdrawn at 5, 15, 30 and 45 min pi. Results: With three sequential loadings (3 × 100 μL) of the Turboflow column, mean coefficients of variation were 1%, below 2%, 2% and 30.9% for matrix effect, specificity, repeatability and intermediate precision, respectively. Correlation coefficients for linearity were superior to 0.97. Limits of detection and quantification of the radiodetector were fixed at 3 and 9 c/s. Retention times for [18F]LBT-999 and the two radiometabolites detected by radio-UHPLC were 6.5, 4.8 and 9.6 min. Forty-five min after the injection, parent fraction was still predominant with 57.8% ± 25% of the total radioactivity. Conclusions: An innovative approach, allying UHPLC and Turboflow column, was developed and its sensitivity, linearity, specificity and repeatability validated. Preliminary results of the clinical trial are in accordance with literature data, demonstrating its efficiency in radiometabolites quantification.

Lysophosphatidylcholine Biomarkers of Lung Cancer Detected by Ultra-performance Liquid Chromatography Coupled with Quadrupole Time-of-flight Mass Spectrometry

Centrifugal ultrafiltration after methanol extraction of whole plasma was used as an optimal condition for the preparation of blood plasma before metabonomic studies. The plasma samples from 102 lung cancer patients and 34 healthy volunteers were prepared with this approach. With ultra-performance liquid chromatography（UPLC） coupled with quadrupole time-of-flight mass spectrometry（Q-TOF MS） analysis, the samples were investigated in order to find potential disease biomarkers. After data acquisition, orthogonal signal correction partial least squares models were built to differentiate the healthy volunteers from lung cancer patients and to identify metabolites that showed significantly different expression between the two groups. Several metabolite ions were identified as potential biomarkers according to the variable importance in the project（VIP） value in both ion modes. Five lysophosphatidylcholines were further identified as specifically lysoPC 16：0, isomer of lysoPC 16：0, lysoPC 18：0, lysoPC 18：1 and lysoPC 18：2. These results suggest that UPLC coupled with Q-TOF MS is an effective technique for the analysis of plasma metabolites in metabonomic studies.

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.

Rapid Determination of Three Kinds of Microcystins in Environmental Water Samples by Disk SPE-Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry

A method of rapidly detecting three kinds of microcystins( MCs) in environmental water samples by using disk SPE- ultra high performance liquid chromatography- tandem mass spectrometry( UPLC- MS / MS) was established. Firstly,environmental water samples were extracted by disk SPE column( C_(18)),and three kinds of MCs were separated by Waters BEH C_(18) chromatographic column with acetonitrile- 0. 2% formic acid solution as the mobile phase. After the gradient elution separation,the external standard method was used for quantitative and qualitative analysis under MRM of UPLC- MS / MS. The results showed that the three kinds of MCs in the range of 0. 05- 10 μg / L showed good linear relation,and the correlation coefficients were higher than 0. 999 4,while the method detection limit was 0. 04 ng / L. Under 0. 1,1,and 5 μg / L standard addition for the same environmental sample,the average recovery was 82. 8%- 108. 8%,and the relative standard deviation of determination results was2. 1%- 10. 1%( n = 6). This method is rapid,sensitive and accurate,so it can be effectively applied in the monitoring of MCs in environmental water samples.

自动QuEChERS结合UPLC-MS/MS测定莲雾中苯并咪唑类农药残留

为了建立自动QuEChERS结合高效液相色谱-串联质谱法测定莲雾中多菌灵、噻菌灵、苯菌灵及甲基硫菌灵4种苯并咪唑类农药残留量的检测方法。将莲雾样品采用混合试剂(5.5 g硫酸镁+1.5 g氯化钠+1.0 g柠檬酸钠+0.5 g柠檬酸二钠)进行净化,经QuEChERS自动样品制备系统进行制备后,应用超高效液相色谱-三重四级杆串联质谱法进行分析。结果表明,4种农药在1.00~10.00 ng/mL质量浓度范围内线性关系良好,决定系数(R2)均大于0.99;0.1、1.0、5.0 mg/kg 3个添加水平下,在莲雾基质中添加回收率为84%~105%,相对标准偏差为0.8%~9.5%(n=3),方法检出限和定量限分别为0.1~0.5μg/kg和0.5~10.0μg/kg。综上,该方法简便省时,净化效果好,灵敏度及准确度高,可用于同时测定莲雾中多菌灵、噻菌灵、苯菌灵及甲基硫菌灵4种苯并咪唑类农药的残留量。

UPLC-MS/MS联合m-PFC测定罗汉果中60种农药残留量

目的:建立罗汉果中60种农药残留的定量筛查方法。方法:样品经乙腈高速匀浆提取、多壁碳纳米管固相萃取小柱净化,采用超高效液相色谱-质谱法,以正、负离子同时扫描的动态多反应监测模式采集数据,采用空白基质匹配法进行定量计算。结果:60种农药线性关系良好,r均大于0.996。其中,59种农药单体的平均回收率为63.9%~108.3%,RSD均小于15%。55批样品中共检出2种禁用农药和12种常用农药。结论:该方法灵敏度高、准确性好,适用于罗汉果中多种农药残留的筛查。

UPLC-MS/MS法检测3种食品中松仁过敏原

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。

UPLC-FLD法测定全血中原卟啉和锌原卟啉

目的建立全血中原卟啉和锌原卟啉的超高效液相色谱-荧光测定方法。方法全血加入间卟啉Ⅸ-二盐酸盐内标,经纯水稀释后,采用二甲基亚砜-丙酮液液萃取进行净化,经C_(18)色谱柱分离,双通道荧光检测器检测,内标法定量。结果原卟啉和锌原卟啉的线性范围均为0.1~5.0μmol/L,相关系数均为0.9995;方法的检出限分别为0.02μmol/L和0.03μmol/L,定量限分别为0.06μmol/L和0.09μmol/L;原卟啉和锌原卟啉在低、中、高三个浓度加标时,方法的加标回收率分别为85.2%~94.7%和84.8%~92.8%;批内精密度(RSD)分别为2.8%~5.3%和2.7%~6.1%,批间精密度(RSD)分别为3.4%~6.3%和3.2%~7.1%;对30份血样中原卟啉与锌原卟啉检测结果分别为:0.1~0.5μmol/L与0.4~1.2μmol/L。结论本方法适用于全血中的原卟啉和锌原卟啉的同时测定。

QuEChERS-UPLC-MS/MS同时测定畜禽肉中23种驱虫类药物残留量

研究旨在建立同时检测畜禽肉中多种驱虫类药物的分析方法,通过优化前处理方法和仪器分析条件,建立了分散固相萃取法-超高效液相色谱-串联质谱法(UPLC-MS/MS)同时测定畜禽肉中23种驱虫类药物残留的分析方法,目标物以乙腈提取,分散固相萃取法(QuEChERS)净化,用乙腈+0.1%甲酸水作为流动相、UPLC-MS/MS确证检测、外标法定量。结果显示:所建立的方法定量限为0.2~1.0μg/kg,回收率为71.4%~107.5%,相对标准偏差为0.9%~8.8%。表明该方法定量限低,稳定性好,适用于畜禽肉中23种驱虫类药物残留的同时检测。

SPE-UPLC联用快速检测保健品中人参皂苷Rh2成分

目的:基于固相萃取与超高液相色谱联用技术,建立一种快速准确检测保健品中人参皂苷Rh2成分的方法,为市售含有人参皂苷Rh2成分的保健品的质量评价提供参考。方法:样品预处理后经甲醇超声提取,中性氧化铝SPE小柱净化,筛选合适的洗脱剂进行HLB-SPE小柱分离纯化,采用WatersT3(100 mm×2.1 mm,1.8μm)色谱柱,乙腈-水为流动相梯度洗脱,PDA全波长扫描,流速0.3 mL·min^(-1)。结果:SPE-UPLC法测得人参皂苷Rh2浓度在9.7~99.8μg·mL^(-1)与其峰面积线性关系良好(r=0.999),平均回收率为99.20%。结论:该方法准确、简便、快速,并能有效去除辅料干扰,稳定性高,可用于含有人参皂苷Rh2有效成分的保健食品的质量控制。

UPLC-Q-Exactive-Orbitrap-MS法同时测定牛黄上清片中18种胆汁酸的含量

目的 建立超高效液相色谱-四极杆-静电场轨道阱高分辨质谱(UPLC-Q-Exactive-Orbitrap-MS)法同时测定牛黄上清片中牛磺胆酸、7-酮-3α,12-α-羟基胆烷酸、甘氨猪去氧胆酸、12-脱氢胆酸、甘氨胆酸、3-酮-7α,12α-二羟基-5β-胆烷酸、牛磺鹅去氧胆酸、3α-羟基-7-氧代-5β-胆烷酸、猪胆酸、牛磺脱氧胆酸钠、猪去氧胆酸、胆酸、甘氨鹅脱氧胆酸、甘氨脱氧胆酸、牛磺石胆酸钠、鹅去氧胆酸、去氧胆酸、石胆酸的含量。方法 分析采用Thermo Fisher Scientfic Bremen HYPERSIL GOLD色谱柱(2.1 mm×100 mm, 1.9μm);流动相0.1%甲酸-甲醇,梯度洗脱;体积流量0.2 mL/min;柱温40℃;加热电喷雾离子源;负离子扫描;平行反应监测模式。再进行化学模式识别。结果 18种胆汁酸在各自范围内线性关系良好(r≥0.999 5),平均加样回收率96.73%~104.07%,RSD 2.10%~4.07%。不同厂家样品中各胆汁酸在种类和含量上存在一定差异。结论 该方法灵敏可靠,专属性好,可用于牛黄上清片的质量控制。

基于硅烷化三聚氰胺海绵的改良QuEChERS结合UPLC-MS/MS快速测定猪肉中49种抗生素多残留

采用十八烷基三氯硅烷(octadecyltrichlorosilane,OTS)与N-[3-(三甲氧基硅基)丙基]乙二胺(N-[3-(trimethoxysilyl)propyl]ethylenediamine,ATS)改性三聚氰胺海绵(melamine sponge,MeS)制备得到2种新型弹性多孔硅烷化MeS(OTS@MeS和ATS@MeS)净化材料,将其用于改良QuEChERS(quick,easy,cheap,effective,rugged and safe)基质净化过程,通过溶液自发浸润和物理挤压过程即可快速、高效分离干扰基质,结合超高效液相色谱-串联质谱技术建立了同时测定猪肉中49种抗生素多残留的分析方法。样品用1.0%乙酸-乙腈溶液提取并用2.0 g Na_(2)SO_(4)和0.5 g NaCl盐析,离心后取1 mL上清液复配使用OTS@MeS与ATS@MeS净化,随后使用Agilent ZORBAX Eclipse Plus C_(18)色谱柱,以甲醇溶液和含有0.1%甲酸、5 mmol/L乙酸铵的甲醇-水溶液(5∶95,V/V)为流动相进行梯度洗脱,采用电喷雾电离源、正离子多反应监测模式进行定性定量分析。结果表明:49种抗生素的相关系数均大于0.999,基质效应为-13.5%~10.9%,检出限在0.1~10μg/kg之间,定量限在0.3~30.3μg/kg之间;利用该方法在低、中、高3个加标水平下进行回收率实验,回收率范围为65.0%~112.7%,日内和日间相对标准偏差分别为0.3%~11.8%和2.4%~18.4%。该方法样品前处理过程简单、快捷、灵敏度高、准确性好,可用于猪肉中49种抗生素多残留的高效快速检测。

固相萃取-UPLC-MS/MS法测定环境水体中多种抗生素

采用固相萃取-超高效液相色谱串联质谱法测定环境水样中25种磺胺类和喹诺酮类抗生素,通过优化试验条件,使方法在2.00μg/L~200μg/L范围内线性良好,方法检出限为1.01 ng/L~2.85 ng/L,7次测定结果的RSD为2.3%~8.0%。将该方法用于自来水和地表水测定,结果均为未检出,高、低质量浓度水平的加标回收率为61.2%~102%。