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《Analytical letters》2012,45(7):1031-1043
Nanoparticles, notable for their small size, high surface area to volume ratios, and strong adsorption capacity, have been the subject of great interest in analytical chemistry. Over the past decade, nanoparticles have been widely used as adsorbents for elemental speciation. Elemental ions or chelates may interact with nanoparticles by van der Waals forces, hydrogen bonds, and hydrophobic interactions. Various types of nanoparticles used for elemental speciation, including magnetic nanoparticles, carbon nanotubes, metallic oxide nanoparticles, nanostructured mixed oxides, and ion imprinted polymer nanoparticles, are reviewed. Future trends and development in this research area are discussed. 相似文献
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土壤样品中砷的形态分析方法研究 总被引:2,自引:0,他引:2
对生态地球化学土壤样品,在Tessier修正顺序提取方法(即七步法)的基础上对提取方法、提取时间、提取溶液的处理方法进行优化选择,用超声法提取水溶态、离子交换态、碳酸盐结合态、腐殖酸结合态、铁锰氧化物结合态、强有机质结合态和残渣态七种形态的砷元素,用原子荧光光谱法测定各个形态砷的含量。优化后的方法测得As元素各形态的检出限均小于1.0μg/g,相对标准偏差(RSD)小于10%,准确度高,质量参数均满足生态地球化学土壤样品评价形态分析的需要。 相似文献
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氟是一种与健康密切相关的必需微量元素,人体对氟的摄入不足或过量都可能会引发健康问题。查明土壤中氟的赋存形态,对了解氟的生物有效性、迁移转化规律及预防氟缺乏或过剩可能导致的生态环境和健康问题具有重要意义。通过讨论,将氟的形态划分为水溶态、吸附态、氧化结合态和固定态。重点研究了固液比、超声时间、超声温度对水溶态氟的提取影响,确定了固液比为1:10、超声时间为30min以及超声温度为25±5℃为最佳提取条件,并在此条件下,开展了弱酸(H2C2O4)、弱碱(NaHCO3)提取剂的先后顺序和不同浓度NH3OHCl-C2H4O2提取液对吸附态氟及氧化结合态氟提取效果的影响。结果表明,土壤的pH对提取吸附态的氟有一定的影响,确定了以酸性土壤使用先碱后酸、碱性土壤使用先酸后碱为吸附态氟的提取顺序;得出了使用0.25mol/L浓度的NH3OHCl - C2H4O2提取液会使氧化结合态氟的提取率更高的结论。所使用的方法精密度RSD/%在3.58% ~ 22.8%之间,准确度RD%在0.42% ~ 10.5%之间,回收率在81.0% ~ 99.2%范围内,均优于区域生态地球化学评价(DZ/T 0289-2015)规范的要求。该方法简单有效,并易于控制,可为研究氟在土壤中的迁移转化提供科学依据。 相似文献
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An analytical method was developed to determine selenoamino acids in the presence of other compounds. Separation has been achieved by High Performance Liquid Chromatography (HPLC) using electrothermal atomic absorption (ETAA) spectrometry as a very sensitive and element-specific detector. On-line HPLC ETAAS speciation of selenocystine and selenomethionine has been studied, using a laboratory made interface. Analytical characterization of the method has been realized with standard solutions. Using a 100μl sample loop, the detection limits were calculated as 8 μgl?1 for selenomethionine and 10 μgl?1 for selenocystine with repeatability and reproducibility of 4% and 7% respectively. The method has been applied to the determination of selenoamino acids in an extract of white clover (CRM402) certified for total selenium. 相似文献
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对近年来联用技术在砷的形态分析中应用的研究成果以及存在的一些问题作了详细的阐述,包括:HPLC-AAS,HPIE-AFS,HPLC-ICP-MS,CZE-ICP-MS和HPLC或CZE与ESI-MS联用。 相似文献
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鱼腥草中Mg的分布及形态研究 总被引:1,自引:0,他引:1
采用原子吸收光谱法对鱼腥草全草中Mg的分布及存在形态进行了研究,得出了对鱼腥草不同部位中微量元素Mg的总含量、提取率、残留率、浸留比以及阳离子、阴离子各形态含量等形态分析的参数,并发现鱼腥草中的微量元素Mg含量丰富,而且大部分Mg的结合形态为阳离子形态,能溶于水。根据实验结果分析Mg可能是鱼腥草的药用有效成分之一。 相似文献
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本文介绍对市售绿茶中Cu、Zn等八种微量元素进行的初级形态分析。在测定煮、泡茶和茶叶残渣中这些元素含量的基础上,算出有关参数,提供了微量元素浸出的有关信息。 相似文献
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土壤样品中汞的形态分析研究进展 总被引:2,自引:0,他引:2
土壤中汞的活性及其生物有效性因其赋存形态不同而存在差异,汞赋存形态分析已成为环境科学领域研究的热点之一。归纳总结了近年来土壤环境中汞赋存形态分类、样品预处理技术和汞形态分析技术研究进展,指出了未来的发展方向。 相似文献
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V. Cerdà J. M. Estela R. Forteza A. Cladera E. Gómez M. T. Oms 《International journal of environmental analytical chemistry》2013,93(1-4):159-178
Abstract The paper reviews several modalities of multicomponent analysis, namely: multilinear regression by using single or multiple standards, non-linear optimization systems by using the Gauss-Newton or the Simplex methods and factor analysis, which have been used by the authors in recent papers. These multicomponent methods have been applied to environmental samples by different analysis techniques, such as UV- visible spectrophotometry, fluorimetry, polarography-voltametry, simultaneous kinetic processes. monitoring of liquid-liquid extraction processes and HPLC (resolution of overlapped peaks). In this way, the advantages and limitations of the methodology of multicomponent analysis are shown. 相似文献
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联用技术测定富硒农产品中硒的形态研究进展 总被引:1,自引:0,他引:1
硒的营养功能与农产品硒的形态息息相关。联用技术作为元素形态分析的有效方法,近年来受到了人们广泛关注。对用联用技术测定富硒农产品中硒的形态研究现状及进展进行了综述,包括前处理技术、色谱分离技术和定量检测方法等3个方面。 相似文献
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金银花中6种金属元素的形态分析 总被引:1,自引:0,他引:1
对金银花中Mn,Fe,Cu,Zn,Ca和Mg6种金属元素的化学形态进行了分析。用传统的煎煮法把元素提取以后,分别采用0.45μm微孔滤膜、LSA-10大孔吸附树脂柱、正辛醇/水分配体系,以区分元素的可溶态和悬浮态、有机态和无机态、醇溶态和水溶态,最后用火焰原子吸收光谱法(FAAS)对湿法消解以后的各种元素进行测定。结果表明,6种元素的提取率在14.97%~48.54%,悬浮态的颗粒吸附率在4.02%~19.84%,加标回收率在96.58%~103.9%,RSD(n=6)≤2.4%。 相似文献
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Experiments have been carried out to study the behaviour of organoarsenicals treated with zeolites by means of speciation
analysis. IC-ICP-MS was applied to identify and quantify arsenite, arsenate and the following organoarsenicals: monomethylarsonic
acid (MMA), dimethylarsinic acid (DMA), trimethylarsine oxide (TMAO), tetramethylarsonium bromide (TMA+), arsenobetaine (AsB) and arsenocholine (AsC). Zeolites loaded with ferrous ions did not significantly increase the retention
of inorganic arsenic species compared to the native zeolites, while there was a ten-fold removal of arsenate relating to arsenite.
The formation of As(V) and DMA in the leachates containing clinoptilolites and mordenites was confirmed in the presence of
natural and synthetic zeolites. Arsenobetaine and arsenocholine yielded higher levels of arsenate than the methylated species. 相似文献