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Matteson S 《Mass spectrometry reviews》2008,27(5):470-484
Accelerator mass spectrometry (AMS) has developed in the last 30 years many notable applications to the spectrometry of radioisotopes, particularly in radiocarbon dating. The instrumentation science of trace element AMS (TEAMS) that analyzes stable isotopes, also called Accelerator SIMS or MegaSIMS, while unique in many features, has also shared in many of these significant advances and has pushed TEAMS sensitivity to concentration levels surpassing many competing mass spectroscopic technologies. This review examines recent instrumentation developments, the capabilities of the new instrumentation and discernable trends for future development. 相似文献
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Regert M 《Mass spectrometry reviews》2011,30(2):177-220
Mass spectrometry (MS) is an essential tool in the field of biomolecular archeology to characterize amorphous organic residues preserved in ancient ceramic vessels. Animal fats of various nature and origin, namely subcutaneous fats of cattle, sheep, goats, pigs, horses, and also of dairy products, are those most commonly identified in organic residues in archeological pottery. Fats and oils of marine origin have also been revealed. Since the first applications of MS coupled with gas chromatography (GC) in archeology at the end of 1980s, several developments have occurred, including isotopic determinations by GC coupled to isotope ratio MS and identification of triacylglycerols (TAGs) structure by soft ionization techniques (ESI and APCI). The combination of these methods provides invaluable insights into the strategies of exploitation of animal products in prehistory. In this review, I focus on the analytical strategies based upon MS that allow elucidation of the structure of biomolecular constituents and determination of their isotopic values to identify the nature of animal fat components preserved in highly complex and degraded archeological matrices. 相似文献
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铜(Cu)是人体内重要的微量金属元素之一,在许多生命过程中扮演着重要角色;同时,铜在人体内受到严格调控,其稳态与人体生理状态密切相关,许多疾病的发生往往伴随着铜代谢失衡的现象。通过监测铜稳态的细微变化,可以更精准地发现导致人体生理异常变化的因素,特别是环境因素对疾病发生及发展的影响。因此,稳定铜同位素分析在环境健康研究中具有广泛的应用前景。多接收器电感耦合等离子体质谱(MC-ICP-MS)是一种强大的同位素分析质谱方法,具有适用范围广、分析精度高等优点,有效促进了铜同位素分析的发展。本文综述了非传统稳定同位素分馏机理及基于MC-ICP-MS的铜同位素分析方法,总结了铜同位素分析在环境健康研究中的主要应用,并对其前景进行展望。 相似文献
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同位素比值质谱与激光吸收光谱分析水中氢氧同位素方法的比较 总被引:3,自引:0,他引:3
氢氧稳定同位素在研究地球水循环过程中发挥着重要作用。本研究采用激光光谱法和高温热转换元素-同位素比值质谱法测定水样中氢同位素,采用激光光谱法和CO2-H2O平衡-同位素比值质谱法测定水样中氧同位素。结果表明:使用原理不同的两种方法测定地下水、海水和大气降水样品,测定的δ2H和δ18O值的精密度与准确度相当,激光光谱法以其快速高效、低成本、样品用量少占有优势;但使用这两种方法测定土壤抽提水样品时,激光光谱法测定δ18O值与真值的偏差为0.34‰,而质谱法测定的偏差小于0.10‰;激光光谱法测定δ2H值与真值的偏差为2.3‰,而质谱法测定的偏差小于0.6‰,说明质谱法的结果明显优于激光光谱法。 相似文献
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通过测定鸡蛋蛋黄的RCF值,说明人工色素和天然色素都可以改变蛋黄的色度,但是通过稳定同位素比值质谱分析发现,鸡蛋中稳定同位素δ13C值仅受日粮中玉米含量的影响,而与加丽素红的添加量无关,据此可以推断蛋黄中色素的来源,从而对蛋鸡生产起到监管作用。本实验选用320只产蛋鸡,分成人工色素组和天然色素组,每组又分成4个实验小组,每个小组做4次重复实验,分别用添加加丽素红的基础日粮和玉米含量不同的基础日粮饲喂63天。采集各组饲料样品,并在实验期的第28天和第56天采集鸡蛋样品,分别测定饲料的稳定同位素δ13C值和蛋黄的RCF值及δ13C值。结果表明:人工色素组,添加或撤除加丽素红,蛋黄的RCF值有极显著变化(P<0.01),但蛋黄中的δ13C值差异不显著(P>0.05);天然色素组,随着日粮中玉米含量的增加或降低,蛋黄的RCF值及δ13C值均有极显著差异(P<0.01),且蛋黄中δ13CC值与日粮中玉米含量呈显著正相关(P<0.05),说明蛋黄中δ13C值主要受日粮中玉米含量的影响。因此,蛋鸡日粮的主要成分决定了鸡蛋蛋黄中碳稳定同位素的组成。 相似文献
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本文通过检验汽车油漆最外层罩光漆的同位素实现不同样品的区分,并考察保存条件对样品同位素的影响。实验共收集了10种汽车罩光漆样品,分别在室温避光、60℃高温、-20℃低温和强紫外线条件下保存6个月,然后用元素分析仪-同位素比值质谱(EA-IRMS)检测样品的碳、氢、氧同位素比值。结果表明:油漆样品在不同保存条件下发生碳、氢、氧同位素分馏,样品的δ13C值在高温和低温保存后向负值偏移,强紫外线照射的影响微弱;δ2H值在3种条件下均向正值偏移,受紫外线照射影响最大;δ18O值在3种条件下均向负值偏移,但不同种类树脂样品之间δ18O值的偏移幅度不同,在3类样品中,聚甲基丙烯酸甲脂类树脂样品分子中由于氧含量最少其偏移值最小。稳定同位素分析方法可为油漆样品分析提供高区分度的三维指纹,在油漆识别与区分方面具有较大的潜力,可用于油漆物证的溯源分析。 相似文献
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To meet the need of the research on isotope effects of mixed hydrogen isotope gas, an analysis method of mixed hydrogen isotope composition was set up through introducing the molecule ionization quotient on MAT253 mass spectrometer. Some effect factors to quotient were examined and the method is used to determine 6 samples of different deuterium concentration. The results show that this method is effective for P2D2 mixed gas and it’s relative standard deviation is more low then 0.3%. 相似文献
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The stable carbon isotope compositions of individual amino acids in muscle tissues of the anchovy, Engraulis japonicus, a key species of animal in the Yellow and the East China Sea ecosystem, were determined by the gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS). Eleven amino acid compounds were identified and their δ(13C) values were successfully measured. The new ability to measure stable carbon isotope compositions of individual amino acids offers a potential method for understanding digest, absorption and metabolism of anchovy, Engraulis japonicus, pathway of carbon transfer through food web and evaluating trophic quality of diet. 相似文献
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用同位素质谱技术发现山西古风化壳型稀土金属矿床 总被引:3,自引:0,他引:3
对山西石炭纪铝土矿中钐 (Sm )和钕 (Nd)元素含量的化学制备和同位素质谱稀释分析方法进行了详细探讨 ,采用固体同位素质谱技术发现了山西古风化壳型稀土金属矿床。可能总稀土的强富集是在本区形成风化壳吸附型轻稀土金属矿床的主要成因。研究结果表明 :在山西沁源大峪和平陆曹川的稀土含量达到风化壳吸附型轻稀土金属和稀土铝土矿矿床工业指标。山西古风化壳型稀土金属矿床是在华北地区首次发现的稀土金属矿床。 相似文献
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Daniel James Wilkinson 《Mass spectrometry reviews》2018,37(1):57-80
Over a century ago, Frederick Soddy provided the first evidence for the existence of isotopes; elements that occupy the same position in the periodic table are essentially chemically identical but differ in mass due to a different number of neutrons within the atomic nucleus. Allied to the discovery of isotopes was the development of some of the first forms of mass spectrometers, driven forward by the Nobel laureates JJ Thomson and FW Aston, enabling the accurate separation, identification, and quantification of the relative abundance of these isotopes. As a result, within a few years, the number of known isotopes both stable and radioactive had greatly increased and there are now over 300 stable or radioisotopes presently known. Unknown at the time, however, was the potential utility of these isotopes within biological disciplines, it was soon discovered that these stable isotopes, particularly those of carbon (13C), nitrogen (15N), oxygen (18O), and hydrogen (2H) could be chemically introduced into organic compounds, such as fatty acids, amino acids, and sugars, and used to “trace” the metabolic fate of these compounds within biological systems. From this important breakthrough, the age of the isotope tracer was born. Over the following 80 yrs, stable isotopes would become a vital tool in not only the biological sciences, but also areas as diverse as forensics, geology, and art. This progress has been almost exclusively driven through the development of new and innovative mass spectrometry equipment from IRMS to GC‐MS to LC‐MS, which has allowed for the accurate quantitation of isotopic abundance within samples of complex matrices. This historical review details the development of stable isotope tracers as metabolic tools, with particular reference to their use in monitoring protein metabolism, highlighting the unique array of tools that are now available for the investigation of protein metabolism in vivo at a whole body down to a single protein level. Importantly, it will detail how this development has been closely aligned to the technological development within the area of mass spectrometry. Without the dedicated development provided by these mass spectrometrists over the past century, the use of stable isotope tracers within the field of protein metabolism would not be as widely applied as it is today, this relationship will no doubt continue to flourish in the future and stable isotope tracers will maintain their importance as a tool within the biological sciences for many years to come. © 2016 The Authors. Mass Spectrometry Reviews Published by Wiley Periodicals, Inc. Mass Spec Rev 相似文献
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干酪根主要由C、H、O和少量S、N组成,作为石油的先驱物,干酪根中各种元素的同位素分析,对于石油形成和分布的研究以及石油的勘探,具有十分重要的意义。目前,干酪根中C的稳定同位素分析开展得较为普遍,而其它各种元素的同位素分析却很少。本文通过仪器实验条件的最佳化实验,建立了干酪根中各种元素的稳定同位素分析方法,用国际原子能机构标样和国家标准物质对各种标气进行了标定。并对方法的准确性和重复性进行了评价。实验说明分析结果满足石油行业标准和有机地球化学研究的要求。 相似文献
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Lung cancer is a devastating illness with an overall poor prognosis. To effectively address this disease, early detection and novel therapeutics are required. Early detection of lung cancer is challenging, in part because of the lack of adequate tumor biomarkers. The goal of this review is to summarize the knowledge of current biomarkers in lung cancer, with a focus on important serum biomarkers. The current knowledge on the known serum cytokines and tumor biomarkers of lung cancer will be presented. Emerging trends and new findings in the search for novel diagnostic and therapeutic tumor biomarkers using proteomics technologies and platforms are emphasized, including recent advances in mass spectrometry to facilitate tumor biomarker discovery program in lung cancer. It is our hope that validation of these new research platforms and technologies will result in improved early detection, prognostication, and finally the treatment of lung cancer with potential novel molecularly targeted therapeutics. 相似文献
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Margaret S. Burns 《Journal of microscopy》1984,135(2):209-212
The use of stable isotopes as tracers for elemental localization is a function of the background count rate which is dependent upon both the natural abundance and the quantity of interferences at the nominal mass. The occurrence of a variable and unpredictable high background count rate at mass 44+ in biological tissue, probably CO2+, limits the usefulness of this isotope for physiological problems. 相似文献
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Lipids, serving as the structural components of cellular membranes, energy storage, and signaling molecules, play the essential and multiple roles in biological functions of mammals. Mass spectrometry (MS) is widely accepted as the first choice for lipid analysis, offering good performance in sensitivity, accuracy, and structural characterization. However, the untargeted qualitative profiling and absolute quantitation of lipids are still challenged by great structural diversity and high structural similarity. In recent decade, chemical derivatization mainly targeting carboxyl group and carbon-carbon double bond of lipids have been developed for lipidomic analysis with diverse advantages: (i) offering more characteristic structural information; (ii) improving the analytical performance, including chromatographic separation and MS sensitivity; (iii) providing one-to-one chemical isotope labeling internal standards based on the isotope derivatization regent in quantitative analysis. Moreover, the chemical derivatization strategy has shown great potential in combination with ion mobility mass spectrometry and ambient mass spectrometry. Herein, we summarized the current states and advances in chemical derivatization-assisted MS techniques for lipidomic analysis, and their strengths and challenges are also given. In summary, the chemical derivatization-based lipidomic approach has become a promising and reliable technique for the analysis of lipidome in complex biological samples. 相似文献
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本文简要介绍了化学测量溯源性和具有绝对测量性质的同位素稀释质谱法(IDMS),并应用该法为国际测量评估计划(IMEP-9)河水样品中的钾提供可直接溯源到SI单位的标准值。 相似文献
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固体同位素质谱计多接收器校正技术 总被引:2,自引:0,他引:2
采用标准电压法和峰跳扫描曲线拟合法分别校正了固体多接收器同位素质谱计各个放大器的放大倍数和法拉第杯接收器的接收效率。结果表明 ,这两种技术的相对标准不确定度分别为 0 .0 0 1 5 %和 0 .0 2 3 % ,可以满足校正的需要 相似文献