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.

Speciation of Volatile Selenium Species in Plants Using Gas Chromatography/Inductively Coupled Plasma Mass Spectrometry

Gas chromatography/inductively coupled plasma mass spectrometry (GC/ICP-MS) coupled with solid phase micro-extraction can provide a simple, extremely selective and sensitive technique for the analysis of volatile sulfur and selenium compounds in the headspace of growing plants. In this work, the technique was used to evaluate the volatilization of selenium in wild-type and genetically-modified Brassica juncea seedlings. By converting toxic inorganic selenium in the soil to less toxic, volatile organic selenium, B. juncea might be useful in bioremediation of selenium contaminated soil.

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.

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.

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.

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

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

在这份报纸，高效的液体层析结合了紫外察觉， Fourier 变换离子回旋加速器回声团 spectrometry (HPLCUV/FTICRMS ) 方法在 moxifloxacin (MOX ) 为杂质侧面的调查被描述药物质和化学参考书物质。十杂质被 HPLCUV 检测，当八杂质被使用与多重阶段的集体度谱的数据和破碎规则相结合的高精确的分子的团识别时。到我们的知识，另外，五杂质在 MOX 药物质第一次被成立。

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

离子色谱—电感耦合等离子体质谱法用于无机硒的形态分析

硒是动物和人体所必需的微量营养元素。硒在基因表达、激素代谢、免疫系统、机体抗氧化中有关键性作用。硒摄入过少会直接导致克山病、大骨节病、心血管等疾病,过量则可能引起中毒。生物体不能自身合成硒,并且直接食用无机硒对人体有害,土壤则成为硒摄入的主要来源,土壤中硒含量与农作物硒含量密切相关(周文辉等,2023)。

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。

微波灰化-高效液相色谱-电感耦合等离子体质谱(ICP-MS)法测定茶叶中的铬酸铅

为了准确测定茶叶中铬酸铅的含量,为市场监管提供判断依据,茶叶样品经微波灰化仪在500℃的条件下灰化50 min后,用0.25 mol/L的NaOH和0.14 mol/L的Na_(2)CO_(3)混合碱性提取液在90~95℃下不间断搅拌提取10 min,提取液经色谱柱分离后,用电感耦合等离子体质谱(ICP-MS)法测定^(52)Cr,建立了微波灰化-高效液相色谱-电感耦合等离子体质谱仪测定茶叶中铬酸铅的方法。研究表明,方法在5.00~500μg/L线性良好,相关系数为0.9998,方法检出限低至2.5 mg/kg,三水平加标回收率为91.3%~95.3%,精密度在1.1%~2.0%。与电炉灼烧茶叶相比,微波灰化具有检出限低、精密度高、准确度良好等特性,能够满足茶叶中铬酸铅的测定。

车用气雾剂中VOCs检测方法的研究

为准确测量气雾剂产品中挥发性有机化合物(VOCs)的成分及含量,设计了特定装置将气雾剂中推进剂和非推进剂进行分离,利用采集袋收集气雾剂中的推进剂,通过液液萃取法对非推进剂中的VOCs进行提取。以所建立的气相色谱-质谱/氢火焰离子化检测器(GC-MS/FID)联用方法对样品进行分析,其中推进剂气体组分含量用归一化法进行测定,非推进剂的VOCs依据检出种类,选择8种VOCs建立标准曲线。各物质在对应质量浓度范围呈良好的线性关系,相关系数(r^(2))均大于0.99;检出限和定量下限分别为0.25~0.50 mg/L和0.50~1.00 mg/L;回收率为90.5%~105%,相对标准偏差(RSD)为1.8%~9.3%。应用建立的方法分析6种不同功能的气雾剂产品,并计算其臭氧生成潜势。结果表明,推进剂部分主要检出丙烷、丁烷、二甲醚,非推进剂部分检出苯系物、烷烃、环烷烃、单萜类、羧酸衍生物、醚类,其中苯系物和单萜类含量较高。该方法可为企业改进产品配方提供参考,也可为监管部门提供技术支持。

基于超声辅助液相萃取-电感耦合等离子体质谱法测定海水中痕量镉

该文建立基于超声辅助液相萃取(ultrasound-assisted liquid phase extraction,UALPE)电感耦合等离子体质谱法(inductively coupled plasma mass spectrometry,ICP MS)的海水样品中镉分析新方法。镉与螯合剂吡咯烷二硫代氨基甲酸铵(ammonium pyrrolidine dithiocarbamate,APDC)反应,在超声辅助下利用四氯化碳萃取生成的螯合物。萃取相经加热烘干后用加入20%HNO3(v/v)和60%H2O2(v/v)反应5 min后,去离子水定容后上机测定。本文考察了影响液相萃取的影响因素和共存离子的干扰情况。在选择的实验条件下,方法的检出限为6.4 ng·L^(-1)。该方法应用于海水样品中痕量Cd的测定,回收率大于90%。与传统的分析方法相比,该方法具有操作简单和成本低廉等优点,并有效消除了传统液液萃取中有机质对分析结果的影响,解决了传统液液萃取和ICP MS兼容性问题。该方法还可拓展至其他重金属元素的痕量分析。

食品中一种新型非法添加物O-丙基伐地那非的快速筛查和定量测定

目的对在食品中发现的一种非法添加的新型磷酸二酯酶5型(phosphodiesterase type 5,PDE-5)抑制剂O-丙基伐地那非进行结构解析并建立定量测定方法。方法采用高效液相色谱-二极管阵列检测器法(high performance liquid chromatography-diode array detector,HPLC-DAD)发现了一种未知的新型伐地那非类似物,采用超高效液相色谱-四极杆-静电场轨道阱高分辨质谱法(ultra performance liquid chromatography-quadrupole/electrostatic field orbitrap high resolution mass spectrometry,UPLC-Q-Orbitrap HRMS)对其结构进行质谱解析,并依据解析的化学结构购买对照品,确定该物质为O-丙基伐地那非。采用超高效液相色谱-三重四极杆质谱法(ultra performance liquid chromatography-coupled triple quadrupole mass spectrometry,UPLC-MS/MS)建立典型食品中O-丙基伐地那非的定量测定方法。结果O-丙基伐地那非在0.50~50.25 ng/mL质量浓度范围内线性关系良好,相关系数(r)为0.9998,方法检出限(S/N=3)为0.02mg/kg,方法的定量限(S/N=10)为0.05mg/kg,在咖啡、压片糖果、保健酒基质中3个水平加样回收率分别为91.8%~93.9%、84.9%~87.3%和95.6%~103.0%,相对标准偏差均不大于4.6%。采用该方法对市场监管部门送检的93批样品进行测定,结果其中17批检出O-丙基伐地那非,其含量为28~359 mg/kg。结论所建立的方法快速、灵敏、准确,可用于O-丙基伐地那非的筛查和定量。本研究思路可给其他非法添加未知物的鉴定提供参考。

IC-ICP-MS联用技术同时测定地表水中砷、铬、汞3种元素不同形态的含量

建立了离子色谱-电感耦合等离子体质谱联用技术同时测定地表水中砷、铬、汞等3种元素8种形态含量的方法。地表水样品用水相滤膜过滤,采用GIST C_(8)(250 mm×4.6 mm,5μm)色谱柱,以0.01 mol/L四丁基氢氧化铵+0.05%L-半胱氨酸+4%甲醇作为淋洗液(pH为6.0,流量为0.9 mL/min),分离样品后进行测定。试验结果表明:三价砷、二甲基砷、一甲基砷、五价砷、无机汞、甲基汞、乙基汞和六价铬可在10 min内得到有效分离,砷、铬、汞的检出限分别为0.075~0.15、0.86、0.00010~0.020μg/L,加标回收率分别为88.8%~108.3%、84.9%、87.7%~96.0%,相对标准偏差分别为1.41%~4.02%、1.82%、0.43%~2.17%。采用该方法检测地表水样品,可满足地表水标准限定值和检测要求。

水中碘化物的3种测定方法比较

目的:通过离子色谱法、硫酸铈催化分光光度法、电感耦合等离子体质谱法3种方法测定水中碘化物,通过实验比较,分析3种方法的优缺点。方法:选取质控样品作为实验对象,按照3种方法实验步骤测定各实验组水中碘化物浓度。结果:3种检测方法线性关系均满足实际检测要求,且相关系数R^(2)≥0.999。电感耦合等离子体质谱法检出限为0.6μg·L^(-1),加标回收率为100.8%,相对标准偏差为0.36%~0.45%;硫酸铈催化分光光度法检出限为1.2μg·L^(-1),加标回收率为84.4%,相对标准偏差为0.80%~1.91%;离子色谱法检出限为8μg·L^(-1),加标回收率为91.4%,相对标准偏差为0.23%~1.11%。结论:3种检测方法检测范围广、灵敏度高,且精密度和准确度表现良好,均可准确测定水中碘化物的含量。

基于iTRAQ技术对低级别胶质瘤与正常脑组织差异性表达蛋白的初步筛选研究

目的应用同位素标记相对和绝对定量(iTRAQ)技术筛选低级别胶质瘤与正常脑组织的差异表达蛋白质。方法将6例低级别胶质瘤实体组织标本与2例正常脑组织标本各自混合后提取总蛋白,进行定量分析和酶解。iTRAQ标记后进行液相色谱-串联质谱(LC-MS/MS)分析。通过Mascot2.9软件进行相关图谱分析。结果有效鉴定出低级别胶质瘤与正常脑组织差异表达蛋白质162个,其中34个上调蛋白质,128个下调蛋白质,这些差异表达蛋白质具有多种生物学活性,参与不同的代谢以及信号通路。结论通过iTRAQ技术可有效鉴定出众多低级别胶质瘤与正常脑组织的差异表达蛋白质,为后续寻找低级别胶质瘤的生物标记物奠定基础。

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.