Rapid Screening of 26 Organophosphorus Pesticides in Fresh Milk by Ultra Liquid Chromatography Coupled With Quadrupole-Time of Flight Mass Spectrometry

[Objectives]A rapid screening and analysis method for 26 organophosphorus agrochemicals in fresh milk was established using ultra performance liquid chromatography coupled with quadrupole-time of flight mass spectrometry.[Methods]Raw milk was extracted with acetonitrile solution containing 0.2%formic acid by volume,and purified with a Dikma ProElut QuECHERS solid phase extraction cartridge.Target compounds were separated on a Waters ACQUITY UPLC HSS T3 chromatographic column(2.1 mm×50 mm,1.8μm)with methanol-water solution as a mobile phase for gradient elution,and through scanning with an electrospray ion source in positive ion mode,26 kinds of organophosphorus agrochemicals could be accurately qualitatively determined within 10 min.[Results]When using formic acid acetonitrile with a volume fraction of 0.2%,there were more types of detected compounds and a greater recovery;and using B cartridge could effectively eliminate the interference of non-polar substances such as phospholipids,achieve higher number of detected compounds than those of A and C,and well separate the 26 kinds of agrochemical residues.[Conclusions]This study provides a reference method for the rapid screening of agrochemical residues in dairy cows in the future.

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.

Measurement of Arsenic Species in Infant Rice Cereals by Liquid Chromatography Inductively Coupled Plasma Mass Spectrometry

Infant rice cereals were analyzed for total arsenic, inorganic arsenic (i-As) and the organic arsenic species monomethylarsonoic acid (MMA) and dimethylarsinic acid (DMA) using liquid chromatography inductively coupled plasma mass spectrometry (LC-ICP-MS). Total arsenic concentrations in the samples ranged from 110 ng/gup to 420 ng/g. The i-As in the rice cereals accounted for 33% to 77% of the total arsenic. The observed variability between infant rice cereals makes a dietary survey approach to accessing arsenic exposures difficult.

Effect of pediatric tuina on hypothalamic metabolites in young rabbits using liquid chromatography-mass spectrometry

Objective: To investigate the changes in the hypothalamic metabolites of lipopolysaccharide(LPS) febrile young rabbits after the treatment with pediatric tuina.Methods: A total of 30 young rabbits were randomly assigned into three groups: the normal group, the model group, and the tuina group. Both the model group and the tuina group were injected intravenously with LPS. “Six antipyretic manipulations”(pushing Tianmen, pushing Kangong, kneading Taiyang,kneading Erhougaogu, clearing Tianheshui, and pushing Jizhu) were administered 1 h after the LPS injection in the tuina group. The rectal temperatures of the young rabbits were monitored during the experiment to explore the antipyretic effect. Three hours after the injection, the content of interleukin-1β(IL-1β), tumor necrosis factor(TNF)-a, and prostaglandin E;(PGE;) in the serum was detected. In addition, liquid chromatography-mass spectrometry(LC-MS) was used for the hypothalamus metabolomics.Results: Compared with the model group, the rectal temperature of the tuina group was decreased at 2 h and 3 h after the LPS injection(P =.04, P =.03, respectively), and the content of IL-1β, TNF-a, and PGE2was decreased(P =.03, P =.003, and P =.008, respectively). The metabolomics results showed that there were 23 potential biomarkers after the tuina intervention, enriching 27 pathways. Lipid metabolites,especially glycerophospholipids, were a majority of the altered metabolites. The primary metabolic pathways affected by tuina included the arachidonic acid metabolism, the GABAergic synapse, D-glutamine and D-glutamate metabolism, and the glutamatergic synapse.Conclusion: Pediatric tuina reduced the temperature of the febrile rabbits and downregulated the expression of IL-1β, TNF-a, and PGE2, and the antipyretic mechanism may be related to changes in metabolites and metabolic pathways in the hypothalamus.

Separation and identification of moxifloxacin impurities in drug substance by high-performance liquid chromatography coupled with ultraviolet detection and Fourier transform ion cyclotron resonance mass spectrometry

In this paper, a high-performance liquid chromatography coupled with ultraviolet detection and Fourier transform-ion cyclotron resonance mass spectrometry （HPLC-UV/FrICRMS） method was described for the investigation of impurity profile in moxifloxacin （MOX） drug substance and chemical reference substance. Ten impurities were detected by HPLC-UV, while eight impurities were identified by using the high accurate molecular mass combined with multiple-stage mass spectrometric data and fragmentation rules. In addition, to our knowledge, five impurities were founded for the first time in MOX drug substance.

COMPREHENSIVE TWO-DIMENSIONAL LIQUID CHROMATOGRAPHY COUPLED WITH QUADRUPLE TIME-OF-FLIGHT MASS SPECTROMETRY FOR CHEMICAL CONSTITUENTS ANALYSIS OF TRIPTERYGIUM GLYCOSIDES TABLETS

Comprehensive two-dimensional liquid chromatography platform(LC×LC)coupled with quadrupole time-of-flight(QTOF)mass spectrometry(MS)is developed to separate,identify and relatively determine the chemical constituents of two types of tripterygium glycosides tablets(TGT).The types and relative contents of the constituents discovered in two kinds of TGT tablets were subsequently compared.C8andC18 column were used for the separation of the first

Pharmacokinetic Comparison of Four Major Bio-Active Components of Naoxintong Capsule in Normal and Acute Blood Stasis Rats Using Ultra-Performance Liquid Chromatography Coupled with Triple-Quadrupole Mass Spectrometry

Objective: To compare the pharmacokinetic differences of the main components of Naoxintong capsule(NXTC) in normal and acute blood stasis rats. Materials and Methods: Rats were subcutaneously injected with adrenaline hydrochloride twice;during the two subcutaneous injections, the rats were placed in ice water for 4 min to reproduce the model rat of acute blood stasis. The normal and acute blood stasis rats were administrated a 5.04 g/kg dose of NXTC suspension. Then, blood samples were collected from the posterior retinal venous plexus at different time points. Plasma concentrations of four major bio-active components including caffeic acid, ferulic acid, formononetin, and tanshinone IIA in NXTC were measured using ultra-performance liquid chromatography coupled with triple-quadrupole mass spectrometry. Phoenix Win Nonlin v6.2 software was used to calculate the pharmacokinetic parameters. Results: Compared with the normal rats, the acute blood stasis rats showed a significant decrease in C_(max) of ferulic acid and formononetin, AUC_(all) of caffeic acid and ferulic acid, and AUC_(INF_obs) of ferulic acid. Conversely, an increase in the Vz_F_obs and MRT_(last) of ferulic acid and caffeic acid was observed. These findings demonstrate that the absorption of the four NXTC components was weakened in the acute blood stasis rats and that the elimination time was prolonged. Conclusions: The significant difference in some parameters of the four NXTC components between the normal and acute blood stasis rats might be caused by an increase in blood viscosity and the subsequent slowing down of blood flow in the acute blood stasis rats. The pharmacokinetic study conducted in pathological state can provide important information and scientific basis for further rational clinical application of NXTC.

Rapid Differentiation of Aconiti Kusnezoffii Radix from Different Geographic Origins Using Ultra-Performance Liquid Chromatography Coupled with Time-of-Flight Mass Spectrometry

Objective:There are different geographic origins of Aconiti Kusnezoffii Radixs(AKRs)sold in the market with different quality.This study aims to establish a rapid analysis method to distinguish the different geographic origins of AKRs and to realize the rapid evaluation of their quality.Methods:An ultra-performance liquid chromatography coupled with time-of-flight mass spectrometry(UPLC-Q-TOF MS)method was utilized to acquire the constituents'information of AKRs from different geographic origins.MSE data and Progenesis QI software were employed to identify the chemical constitutes.Principal component analysis(PCA)was applied to comparing MS data to find the chemical markers of AKRs from different geographic origins.Results:Twenty-three components were detected and 17 out of them were identified,including diester-diterpenoid alkaloids,monoester-diterpenoid alkaloids,and amine-diterpenoid alkaloids.Three pairs of isomers were detected and two of them were distinguished by the retention time of standard samples.Thirteen chemical markers were screened out through PCA and orthogonal partial least square discriminant analysis.Through detecting Napelline or isomer of Napelline(m/z 360.2530)and Aconifine(m/z 662.3170),AKRs from inner Mongolia autonomous could be screened.According to the existence of benzoylaconine(m/z 604.3108)and Indaconitine(m/z 630.3159),it could be confirmed that the AKRs are from Xinjiang Uygur autonomous.AKRs that cannot detect compounds above-mentioned could be from Liaoning or Shanxi Province.Conclusions:The chemical profile could be used not only to distinguish the AKRs from different geographic origins but also to identify the true and false of AKRs.This study lays a foundation for the study of efficacy and toxic of AKRs.

GLOBAL ANALYSIS OF THE METABOLITES OF CURCUMIN IN RATS BY ULTRA PERFORMANCE LIQUID CHROMATOGRAPHY COUPLED WITH QUADRUPOLE TIME OF-FLIGHT TANDEM MASS SPECTROMETRY

Curcumin,a safe natural yellow pigment with a wide range of pharmacological activities,is used both in herbal drugs and as a food coloring agents.Studies have shown that curcumin would suffer from extensive metabolism in vivoand the predominant metabolic pathways are reduction and conjugation.In order to comprehensively study the metabolism and enrich the metabolic profile of cxurcumin in vivo,we carried out this research.A systematic method with highly sensitive UPLC-Q/TOF-MS was established to analyze different biological samples of rats after

A rapid and simple ultraperformance liquid chromatography coupled to tandem mass spectrometry(UPLC-MS/MS) method for the detection of glucuronic acid-conjugated steroid metabolites

In the present study, we effectively detected 10 steroids and glucuronic acid-conjugated steroid metabolites in 12 min by ultraperformance liquid chromatography coupled to tandem mass spectrometry （UPLC-MS/MS）. Steroids testosterone （T）, 5ct-dihydrotestosterone （DHT）, androsterone （ADT）, etiocholanolone （ETIO）, estradiol （E2） and their glucuronide conjugates were well-separated on an Eclipse Plus C18 column （2.1 mm×50 ram, RRHD 1.8μm）. The mobile phase consisted of a mixture of methanol and ultrapure water （containing I mM ammonium formate） at a ratio of 60：40 （v/v）, and the flow rate was set at 0.25 mL/min. The LC eluate was detected by electrospray ionization （ESI） source in both positive and negative ion modes. Neutral loss （NL of 176, 194, 211 and 229 Da in positive mode） and precursor ion （PI ofm/z 141,159 and 177 in positive mode and 75, 85 and 133 in negative mode） methods were applied for the detection of steroid glucuronides. The multiple reaction monitoring （MRM） transitions were m/z 289.3→97.1,291.3→105, 291.3→199.2, 273.2→145.4 and 255.2→159.1 for T, DHT, ADT, ETIO and E2 in positive mode, respectively; as well as m/z 463.3→85 for T glucuronide （T-G）, m/z 465.3→75 for DHT glucuronide （DHT-G）, ADT glucuronide （ADT-G）, ETIO glucuronide （ETIO-G） and m/z 447.3→271 for E2 glucuronide （Ez-G） in negative mode. In addition, the analytical method was also applied for the detection of steroid glucuronides in pooled human liver microsomes （HLM）, which might serve as a basis for further investigation of steroid metabolism in vivo and in vitro.

Rapid Determination of Tetrodotoxin in Human Plasma by Ultra Performance Liquid Chromatography-Tandem Mass Spectrometry

A sensitive analytical method was developed to determine tetrodotoxin（TTX） in human plasma samples using protein precipitation, followed by ultra performance liquid chromatography（UPLC） analysis coupled with tandem mass spectrometry（MS/MS） using 11-deoxytetrodotoxin（11-deoxyTTX） as an internal standard. The plasma samples were prepared using protein precipitation prior to being analyzed by UPLC-MSfMS to identify TTX over a zwitterionic-hydrophilic interaction liquid chromatography column. The retention time values of TTX and 11-deoxyTTX were 4.12 and 3.67 min, respectively. TTX and 11-deoxyTTX were monitored and quantitated on the basis of their ion transitions for their respective precursor ions to their product ions（i.e., m/z 320.0→162. l for TTX and m/z 304.0→176.0 for 11-deoxyTTX） in the multiple reaction-monitoring mode. The lower limit of quantification of this method was determined to be 0.0199 ug/mL. This method showed good linearity for plasma samples that contained TTX concentrations in the range of 0.0199--1.99 ng/mL. The specificity, precision, accuracy, matrix effect, and stability characteristics of this method were also examined. The intra-assay precision and accuracy ranged from 1.89% to 6.00% and from 92.21% to 100.00%, whereas the inter-assay precision and accuracy ranged from 0.64% to 7.75% and from 99.38% to 101.26%, respectively. This new method therefore represents a rapid, accurate, reliable, and highly sensitive method for the qualitative and quantitative analyses of a trace amount of TTX in human plasma samples.

土壤中Sb(Ⅲ)和Sb(Ⅴ)的有效提取与测定

锑的各种形态中三价锑和五价锑的毒性较高,在城市土壤锑组成中占比也较高。研究了萃取方式、萃取剂、萃取条件、色谱分离流动相条件等因素对土壤中价态锑提取和分析的影响,建立了完整的土壤价态锑萃取-分析方法。研究推荐以柠檬酸溶液为萃取剂,70℃恒温振荡萃取的方式提取价态锑,萃取液以乙二胺四乙酸二钾+邻苯二甲酸为流动相,经色谱分离后利用电感耦合等离子体质谱仪对不同价态的Sb进行分析。所建立的方法检出限低,准确性精密度好,可用于实际土壤样品中价态锑的有效提取与测定。

QuEChERS EMR-Lipid净化结合同位素稀释-超高效液相色谱-串联质谱法同时测定蜂房及其制剂中10种真菌毒素

目的 建立一种Qu ECh ERS EMR-Lipid净化结合同位素稀释-超高效液相色谱-串联质谱技术(UPLC-MS/MS)同时测定蜂房及其制剂中10种真菌毒素的检测方法。方法 样品经80%乙腈水溶液提取,Qu ECh ERS EMRLipid净化,采用UPLC-MS/MS,在多反应监测(MRM)模式下进行测定,内标法定量。结果 10种真菌毒素含量在各自质量浓度范围内具有较好的线性关系(r>0.999),目标化合物在低、中、高3个质量浓度下的平均回收率为83.8%~107.1%(RSD<6.5%),定量限(LOQ)为0.18~129μg/kg。结论 该法前处理步骤简便,净化效果良好,提高了样品检测效率,内标法定量精准可靠,适用于蜂房及其制剂中10种真菌毒素的同时检测。

基于非靶标代谢组学策略足三里电针干预胃热证作用机制研究

目的:研究足三里电针对胃热证大鼠的防治作用。方法:采用干姜水煎液连续灌胃2周建立胃热证大鼠模型,造模期间以足三里电针对大鼠进行干预,测定大鼠体征参数、血液生化参数,基于高分辨飞行时间液质联用仪进行非靶标代谢组学分析,选择VIP值大于1.5的差异性代谢物进行鉴定,确定相关代谢通路。结果:足三里电针对胃热证大鼠具有显著的防治作用,包括改善大鼠体征各项参数、血液生化指标,代谢组学分析结果筛选并鉴定与胃热证病理过程和电针干预调控作用相关的8个差异性代谢物,其干预机制涉及的主要代谢通路包括鞘磷脂代谢、氨基酸合成、炎症代谢。结论:足三里电针能够改善大鼠胃热证的各项指标,其干预机制涉及鞘磷脂代谢、氨基酸合成、炎症代谢,为足三里电针防治胃病的机制研究提供了一定的科学依据。

基于LC-MS/MS测定人体类固醇激素的研究进展

类固醇激素是一类具有环戊烷多氢菲结构的化合物,由细胞色素P450酶催化形成,在调节机体代谢、促进性器官发育等方面起着重要作用。临床上将类固醇激素水平作为肾上腺疾病、精神类疾病等的诊断指标。液相色谱-串联质谱(LC-MS/MS)联用技术因具有高灵敏度、高通量和高专属性的特点,已成为类固醇临床测定的首选方法。本文综述了LC-MS/MS在内源性类固醇激素测定中的应用,特别是在样品前处理、色谱条件和质谱条件优化等方面的研究进展,为临床上类固醇激素的诊断检测提供参考。

不同品种生菜的多酚、黄酮差异比较与抗氧化活性

生菜富含多种酚酸、黄酮类化合物,是获取膳食多酚的良好食物来源。本研究对50个不同品种(34种绿色品种和16种红色品种)生菜中的总酚、总黄酮含量及其抗氧化能力进行测定,同时采用超高效液相色谱-四极杆-飞行时间质谱法和超高效液相色谱法对生菜中17种特征酚酸和黄酮类化合物进行鉴定及含量测定,再结合多元统计分析进行分类和相关性分析。结果表明,红色品种生菜的总酚、总黄酮含量及抗氧化能力高于绿色品种生菜;50种生菜中鉴定出绿原酸、咖啡酸、异绿原酸A/B、菊苣酸、木犀草素-7-O-β-D-葡萄糖醛酸苷、槲皮素-3-O-葡萄糖酸苷和槲皮素-3-O-葡萄糖苷7种多酚类化合物,整体在红色品种生菜中含量更高。多元统计分析结果表明绿原酸、木犀草素-7-O-β-D-葡萄糖醛酸苷和槲皮素-3-O-葡萄糖苷与抗氧化能力的相关性较高。综上,G21K104、W3088、H20K6457等5个红色新品种及商业种,G21K212、G21K117等4个绿色新品种为高抗氧化活性生菜品种。本研究可为生菜育种、种质资源创新和营养健康、功能性产品开发提供参考依据。

梯度洗脱LC-ICP/MS法测定5种硒形态

建立一种梯度洗脱液相色谱-电感耦合等离子体质谱法(Liquid Chromatography-Inductively Coupled Plasma-Mass Spectrometry,LC-ICP/MS)分析硒代胱氨酸、甲基硒代半胱氨酸、亚硒酸根、硒代蛋氨酸、硒酸根5种硒形态。样品通过Hamilton PRP-X100阴离子色谱柱,分别以流动相A 40 mmol·L^(-1)磷酸氢二铵+5 mmol·L^(-1)柠檬酸(pH=4.6)和流动相B 60 mmol·L^(-1)磷酸氢二铵+5 mmol·L^(-1)柠檬酸(pH=4.6)梯度洗脱5种硒形态,流速为1.0 mL·min^(-1),切换时间分别为3.0 min和6.4 min,ICP/MS检测,外标法定量。5种硒形态在8.5 min内检测完毕;0.5~200.0μg·L^(-1)相关系数r>0.999,最低检测质量浓度为0.10~0.39μg·L^(-1)。相较于《生活饮用水标准检验方法第6部分:金属和类金属指标》(GB/T 5750.6-2023)硒形态分析法,该方法将分析时间缩短了46.8%,5种形态峰分离度更好、灵敏度更高。

液相色谱-质谱技术结合网络药理学研究附子-葶苈子药对的抗心力衰竭作用机制

采用超高效液相色谱-四极杆-飞行时间串联质谱(UPLC-Q TOF MS^(E))技术,结合UNIFI软件对附子-葶苈子药对水煎液中的化学成分进行分析鉴定。首先,在UPLC-Q TOF MS^(E)正、负离子模式下采集质谱数据,使用UNIFI软件对化合物精确相对分子质量和串联质谱数据进行辅助解析,结合对照品的质谱信息及相关参考文献,从附子-葶苈子共煎液中共鉴定出142个化合物。以这些成分为候选化合物,采用网络药理学方法,构建了“药物-成分-靶点”关键网络,筛选出附子-葶苈子药对治疗心力衰竭的10个关键靶点,分别为BCL2、IL6、STAT3、CASP3、PPARG、ESR1、EGFR、AKT1、MMP9、PTGS2,它们主要参与调控糖尿病并发症中的AGE-RAGE信号通路、表皮生长因子受体信号通路以及缺氧诱导因子信号通路等;活性成分包括水黄皮素、山柰酚、异鼠李素等黄酮类和惰碱、德尔妥因等生物碱类以及穿心莲内酯类化合物。该研究揭示了附子-葶苈子配伍抗心力衰竭的潜在作用机制,为该药对的临床应用提供了科学依据。

亲脂性匹配色谱分离-超高效液相色谱-串联质谱法测定果蔬中21种三唑类杀菌剂

为了提高农药残留的色谱分离效率和降低基质效应,本研究提出亲脂性匹配色谱分离,选取三唑类杀菌剂为研究对象,建立了果蔬中21种三唑类杀菌剂的超高效液相色谱-串联质谱(Ultra performance liquid chromatography-tandem mass spectrometry,UPLC-MS/MS)检测方法。样品经乙腈提取,盐析分相,分散固相萃取净化,选用与三唑类杀菌剂具有相近亲脂性的色谱柱进行分离,探究不同亲脂性烷基键合相对基质效应、回收率以及三唑杀菌剂和基质组分色谱分离的影响。结果表明,亲脂性匹配色谱分离能够提高色谱分离效率,改善三唑杀菌剂和基质组分的色谱分离,21种三唑杀菌剂的基质效应为-8.3%~4.7%,在5~250μg/L浓度范围内线性关系良好,决定系数R2≥0.999,平均回收率为91.4%~108.1%,定量限为0.5~3.5μg/kg。该检测方法能够有效降低基质效应,使用溶剂校准曲线进行定量即可获得满意的回收率,显著提高了检测效率,具有简便、准确、灵敏度高等特点,适用于果蔬中三唑杀菌剂的检测。所述亲脂性匹配色谱分离,为农药残留的液相色谱-串联质谱法分析中液相色谱柱的选择和基质效应的降低提供了方法参考。

清瘟护肺颗粒化学成分研究

目的研究清瘟护肺颗粒的化学成分。方法查阅中国知网、PubMed、Web of Science等数据库,检索该制剂组方药材化学成分的相关文献,结合文献报道和ChemicalBook数据库信息,建立化学成分数据库。采用超高效液相色谱-四极杆/静电场轨道阱高分辨质谱(UHPLC-Q Exactive Focus MS/MS)法分析制剂的图谱数据,并以Xcalibur 4.0软件拟合分子式,与自建数据库信息进行匹配,初步推测分子式信息,与ChemicalBook或ChemSpider数据库比对,推测化学成分结构。结果共鉴定出158个化学成分,包括苷类36个,黄酮类29个,苯丙素类28个,有机酸类18个,萜类17个,色原酮类8个,其他类22个。结论所建立的方法可系统、准确、快速地定性分析清瘟护肺颗粒中的化学成分。