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41.
42.
该文建立了用微波消解-电感耦合等离子体质谱仪(ICP-MS)同时分析玛咖中锂(Li),铍(Be),硼(B),镁(Mg),铝(Al),钪(Sc),钛(Ti),钒(V),铬(Cr),锰(Mn),铁(Fe),钴(Co),镍(Ni),铜(Cu),锌(Zn),镓(Ga),砷(As),锶(Sr),钼(Mo),镉(Cd),锡(Sn),锑(Sb),钡(Ba),镧(La),汞(Hg),铅(Pb),铋(Bi)共27种元素的方法。样品经微波消解后,利用ICP-MS测定上述元素,以内标法改善基体效应及干扰,通过标准曲线计算含量。实验结果表明所有元素的线性关系良好,相关系数(r)为0.999 4~1.000 0(Hg为0.998 2);检出限为0.003~ 2.662 μg·L-1;重复性的相对标准偏差(RSD)大多数小于5%(个别元素除外);加样回收率为78.5%~123.7%, RSD大多数小于5%(个别元素除外);标准物质中27个元素的测定值基本都在标准值范围内(个别元素除外)。该方法灵敏度高,专属性好,重复性好,分析速度快,适用于玛咖中多种元素的含量测定,为玛咖的质量控制提供参考依据。 相似文献
43.
目的 建立电感耦合等离子体质谱快速测定黄芪注射液中铅、砷和镉的分析方法.方法 样品经过微波消解,以锗、铟、铋作为内标,以茶叶标准物质作为质控,采用ICP-MS测定上述3种元素.结果 3种元素在0.5 ng·mL-1~50 ng·mL-1浓度范围内线性良好,r值均大于0.999 5,回收率为91.5%~102.6%,RSD均小于4.7%.结论 本方法简单、快速,结果准确可靠,适用于黄芪注射液中上述3种元素的测定. 相似文献
44.
目的利用DRC-ICP-MS,建立快速监测尿液中19种元素(Be、Rb、Sr、Cd、Pb、Cs、Tl、V、Cr、Mn、Ni、Co、Cu、Zn、Sn、Sb、Te、As和Se)的检测方法。方法尿液样品经过1∶20稀释后上机检测,采用DRC模式消除干扰,检测元素V51、Cr52、Mn55、Ni58、Co59、Cu63、Zn64、Sn120、Sb121、Te130、As75和Se80,其余元素采用标准模式检测。结果 19种元素(Be9、V51、Cr52、Mn55、Ni58、Co59、Cu63、Zn64、As75、Se80、Rb85、Sr88、Cd114、Sn120、Sb121、Te130、Cs133、Tl205和Pb208)的方法检出限分别为2.7、2.0、2.7、1.5、3.9、0.8、5.8、35.3、32.4、21.1、1.4、4.2、1.1、9.1、1.1、8.6、0.1、0.2和1.0ng/L,方法的精密度在3%以内。结论该检测方法准确快速,前处理简便,样品用量少,检测成本低,适合大量样本的快速筛查和监测。 相似文献
45.
K. Osman J. E. Zejda A. Schütz D. Mielzynska C. G. Elinder M. Vahter 《International archives of occupational and environmental health》1998,71(3):180-186
Objectives: To assess the exposure to toxic metals and to evaluate its possible association with essential elements and socioeconomic
status in children from the town of Bytom in the Katowice area; this area is one of the most polluted industrialized regions
in Poland. Methods: Concentrations of lead, cadmium, mercury, selenium, magnesium, copper, and zinc were determined in whole blood of 211 children
aged 9 years. The samples were analyzed using inductively coupled plasma mass spectrometry (ICP-MS). Information on socioeconomic
factors was collected using questionnaires. Concentrations of trace elements in the blood of 24 Swedish children aged 9–10
years were used for comparisons. Results: The concentrations of lead detected in the blood of the Polish children ranged from 0.09 to 1.9 μmol/l, with the median
value being 0.27 μmol/l. Statistically significant associations were found between lead and such socioeconomic factors as
the number of siblings, trips outside the region, maternal smoking, playing outdoors, and apartment standard. The average
blood lead level was about 3 times higher in the Polish children than in the Swedish group. The median blood concentration
of cadmium found in the Polish children was 3.4 nmol/l (range 1.1–41 nmol/l; almost 3 times higher than that detected in the
Swedish children), and that of mercury was 3 nmol/l (range 0.5–11 nmol/l). The median blood levels and ranges of the essential
elements were 1.1 (0.7–2.0) μmol/l for selenium, 1.5 (1.2–1.9) mmol/l for magnesium, 17 (13–22) μmol/l for copper, and 78
(54–104) μmol/l for zinc, respectively. The concentrations of selenium and magnesium were significantly lower in the Polish
group as compared with the Swedish children. Conclusions: In all, 7% of the Polish children had blood lead levels exceeding 0.5 μmol/l, the concentration above which negative effects
on mental development have been reported. However, the findings indicate a decrease in lead exposure during recent years among
the Bytom children.
Received: 26 June 1997 / Accepted: 28 August 1997 相似文献
46.
微波消解/ICP-MS法测定胎儿肾脏和小脑中稀土元素的研究 总被引:2,自引:0,他引:2
目的 测定深圳市正常中期引产胎儿肾脏和小脑中多种稀土元素的含量 ,为研究人类生命不同阶段稀土元素水平提供基础资料。方法 样品经HNO3+H2 O2 微波消解系统消解后 ,用电感耦合等离子质谱(ICP MS)检测胎儿肾脏和小脑中La、Ce、Pr、Nd、Sm、Eu、Gd、Tb、Dy、Ho、Er、Tm、Yb、Lu 14种稀土元素。结果 所检测的 14种稀土元素 ,La在肾脏中的含量最高为 0 4 2 0 μg kg,Ce在小脑中的含量最高为 0 .36 3μg kg,Yb在肾脏和小脑中的含量均最低 ,分别为 0 . 10 3μg kg和 0. 0 98μg kg。在胎儿肾脏和小脑中 ,轻稀土元素 (La~Sm)的总含量分别为 1 .4 2 7μg kg、1. 2 36 μg kg ,中稀土元素 (Eu~Gd)的总含量分别为 0 . 4 6 9μg kg、0 .4 32 μg kg ,重稀土元素 (Tb~Lu)的总含量分别为 1 .387μg kg、1 .4 18μg kg。 结论 上述 14种稀土元素均可在胎儿肾脏和小脑中检出 ,并具有一定的分布特点。 相似文献
47.
P. Schramel I. Wendler J. Angerer 《International archives of occupational and environmental health》1997,69(3):219-223
Objective: An analytical method has been established to determine the concentration of antimony (Sb), bismuth (Bi), lead (Pb), cadmium
(Cd), mercury (Hg), palladium (Pd), platinum (Pt), tellurium (Te), tin (Sn), thallium (Tl) and tungsten (W) in urine. The
aim was to develop a method which is equally suitable for the determination of environmentally as well as occupationally caused
metal excretion. Methods: Inductively coupled plasma-mass spectroscopy (ICP-MS) was used for the determination of metals. Calibration was done using
aqueous solutions and standard addition respectively. Results: Urine samples of 14 persons occupationally non-exposed to metals were analysed. With the exception of Pt and Bi all the
metals were found in these urine samples. The detection limits for these metals lie between 5 and 50 ng/l. Conclusions: For some metals, which are important from an occupational as well as an environmental viewpoint, ICP-MS is more sensitive
than atomic absorption spectrometry (AAS). ICP-MS, moreover, is welcome as a reference method for AAS with the additional
advantage of multi-element measurement.
Received: 5 February 1996/Accepted: 23 August 1996 相似文献
48.
49.
Recent advances in material science and chemistry have led to the development of nanoparticles with diverse physicochemical properties, e.g. size, charge, shape, and surface chemistry. Evaluating which physicochemical properties are best for imaging and therapeutic studies is challenging not only because of the multitude of samples to evaluate, but also because of the large experimental variability associated with in vivo studies (e.g. differences in tumor size, injected dose, subject weight, etc.). To address this issue, we have developed a lanthanide-doped nanoparticle system and analytical method that allows for the quantitative comparison of multiple nanoparticle compositions simultaneously. Specifically, superparamagnetic iron oxide (SPIO) with a range of different sizes and charges were synthesized, each with a unique lanthanide dopant. Following the simultaneous injection of the various SPIO compositions into tumor-bearing mice, inductively coupled plasma mass spectroscopy (ICP-MS) was used to quantitatively and orthogonally assess the concentration of each SPIO composition in serial blood samples and the resected tumor and organs. The method proved generalizable to other nanoparticle platforms, including dendrimers, liposomes, and polymersomes. This approach provides a simple, cost-effective, and non-radiative method to quantitatively compare tumor localization, biodistribution, and blood clearance of more than 10 nanoparticle compositions simultaneously, removing subject-to-subject variability. 相似文献
50.