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1.
A 3-laboratory method trial was conducted to evaluate 2 sample digestion procedures and instrumental determination parameters for analysis of calcium and lead in Ca supplements. Calcium supplements were treated by dry-ash digestion or microwave dissolution prior to spectrometric analysis. In each case, Pb was determined by graphite furnace atomic absorption spectrometry and Ca by inductively coupled plasma-atomic emission spectrometry. Blind duplicates of 6 Ca supplement samples were analyzed after each sample treatment procedure. Matrix pairs contained dissimilar Pb levels to cover the analyte range encountered during method development. Calcium content of the Ca supplement samples also reflected the range seen during method development. Stock solutions of Ca and Pb were supplied to collaborators for preparation of quantitation standards to remove a variable external to the method. National Institute of Standards and Technology Standard Reference Material (NIST SRM) 1486, bone meal, was included to assess method accuracy and recovery at NIST certificate Ca and Pb levels for this material (26.58 +/- 0.24% Ca and 1.335 +/- 0.014 micrograms Pb/g). Analyses of the NIST SRM yielded 25.9 +/- 1.1 and 27.2 +/- 2.3% Ca and 1.53 +/- 0.19 and 1.26 +/- 0.19 micrograms Pb/g for dry-ash and microwave procedures, respectively. Statistical analyses of data indicated acceptable repeatability and reproducibility for determination of Pb and Ca in various Ca supplements. With either sample preparation technique, the method is appropriate for determining Pb or Ca in Ca supplements.  相似文献   

2.
A fully automated on-line sample pretreatment system combining microwave digestion with sample preconcentration/matrix separation for the determination of trace metals (Fe, Ni, Cu, Zn, and Pb) in blood and serum samples by inductively coupled plasma mass spectrometry (ICPMS) was designed and evaluated. The samples were mixed with an appropriate reagent and digested in a flow-through, focused microwave-heated oven. After digestion, the sample solution was transferred on-line to a column packed with iminodiacetate-based resin for separation of matrix elements like Na, K, Ca, Mg, Cl, P, and S that might interfere with the measurement by ICPMS. The analytes chelated on the resin were subsequently eluted and led to ICPMS for multielement determination. The whole sample pretreatment process was automatically controlled by a self-designed expert system. The analytical reliability of data from this on-line system was confirmed to be good with the analysis of SRM samples (Seronorm Whole Blood and NIST SRM 1598 Bovine Serum), and the limits of detection (3 sigma) for Fe, Ni, Cu, Zn, and Pb were 68, 0.34, 3.5, 13.4, and 0.22 microgram/L, respectively. With this fully automated on-line system, the determination of analytes in biological fluid samples down to micrograms-per-liter levels has been proven to be feasible, and the sample throughput can achieve up to 6 samples/h.  相似文献   

3.
OBJECTIVE: The present study was initiated to investigate the validity of cadmium (Cd) and lead (Pb) in urine in comparison with the metals in blood as a biological marker of nonoccupational exposure of general populations to these metals as environmental pollutants. DESIGN: Peripheral blood samples, morning spot-urine samples, and 24-h total food duplicate samples were collected from 107 nonsmoking women (aged 30-59 years) in four urban and rural survey sites in Korea. METHODS: Portions of the samples were digested by heating in the presence of mineral acids, and the digests were analyzed for Cd and Pb by graphite furnace atomic absorption spectrophotometry. The metal concentrations in urine were adjusted for creatinine concentration and a specific gravity of 1.016. The analyte levels were evaluated on an individual basis (n = 107) and also on a group basis, i.e., in terms of geometric means for the survey sites (n = 4). RESULTS: Cd in urine correlated with Cd in blood on an individual as well as survey-site basis and tended to correlate with Cd in food duplicates on a group basis. The correlation of Pb in urine with Pb in blood was weaker than that of Cd in urine with Cd in blood when evaluated on an individual and survey-site basis. Pb in urine correlated with Pb in food duplicates either weakly or even negatively when examined on a survey-site basis. CONCLUSIONS: Cd in urine proved to be valid as a biological marker of environmental exposure of general populations, whereas less support was obtained for Pb in urine as an exposure marker.  相似文献   

4.
用石墨炉原子吸收光谱法测定土壤样品中Pb和Cd时,有时候直接按照方法标准GB/T 17141—1997操作,测定结果不能满足质控要求。研究结果表明,目标元素系列标准溶液中,分别含和不含土壤基体元素Na、Mg、Al、Si、Fe、Ca等元素混合成分时,校准曲线斜率明显不同。为减小基体效应的影响,基于文献调研和实验结果,对上述方法标准实验步骤进行了下列改进:(1)取相同体积实际样品消解液混合后,定量加入到用于建立校准曲线的系列标准溶液中,用于基体匹配;(2)对消解液进行适度稀释,仍采用标准溶液建立校准曲线。用4个土壤标样和土壤样品加标测定结果对改进后的方法进行了验证,结果表明,基体稀释法测定Pb的回收率范围分别为90.4%~114%;测定低含量Cd时,回收率范围为84.1%~125%。基体匹配法测定Pb和Cd的回收率范围分别为93.0%~105%和102%~119%,基本满足土壤样品中重金属回收率为80%~120%的质控要求。样品中痕量镉在测定下限附近时,应严格控制稀释倍数,或采用基体匹配法测定。改进后的操作步骤适合日常检测工作中大批量土壤样品中Pb和Cd的准确测定。  相似文献   

5.
用石墨炉原子吸收光谱法测定土壤样品中Pb和Cd时,有时候直接按照方法标准GB/T 17141—1997操作,测定结果不能满足质控要求。研究结果表明,目标元素系列标准溶液中,分别含和不含土壤基体元素Na、Mg、Al、Si、Fe、Ca等元素混合成分时,校准曲线斜率明显不同。为减小基体效应的影响,基于文献调研和实验结果,对上述方法标准实验步骤进行了下列改进:(1)取相同体积实际样品消解液混合后,定量加入到用于建立校准曲线的系列标准溶液中,用于基体匹配;(2)对消解液进行适度稀释,仍采用标准溶液建立校准曲线。用4个土壤标样和土壤样品加标测定结果对改进后的方法进行了验证,结果表明,基体稀释法测定Pb的回收率范围分别为90.4%~114%;测定低含量Cd时,回收率范围为84.1%~125%。基体匹配法测定Pb和Cd的回收率范围分别为93.0%~105%和102%~119%,基本满足土壤样品中重金属回收率为80%~120%的质控要求。样品中痕量镉在测定下限附近时,应严格控制稀释倍数,或采用基体匹配法测定。改进后的操作步骤适合日常检测工作中大批量土壤样品中Pb和Cd的准确测定。  相似文献   

6.
周伟  贾云海 《冶金分析》2007,27(10):1-1
提出了电感耦合等离子体原子发射光谱法测定锌及锌合金中铝、铋、钙、镉、钴、铬、铜、铁、镁、锰、钼、镍、铅、锡、钛和钒16种元素的分析方法,对仪器各项参数进行优化,采用基体匹配办法克服基体干扰,通过选择合适的分析线和背景校正消除共存元素间干扰。方法应用于实际样品分析,测定结果与认定值或其他方法的测定值相符。  相似文献   

7.
A published procedure for the liquid-liquid extraction of Cd by sodium diethyldithiocarbamate (NaDDC) was modified and tested on 12 biological matrixes of plant and animal origin for use with isotope dilution (ID) inductively coupled plasma mass spectrometry (ICPMS). The tested matrixes were reference materials, certified for Cd, and a feces in-house standard. The digested and extracted standards were analyzed for Cd stable isotopes by ICPMS and the resulting isotope ratios examined for isobaric and polyatomic interferences. Cadmium recoveries, after extraction, ranged from 73% to 20% and apparently were inversely related to Cd concentration, even in the presence of excess chelator. For each reference material, the measured isotope ratios for Cd were corrected for instrumental bias and compared to natural abundance Cd isotope ratios. Nonextracted samples had large isotope ratio deviations for all but one or two ratios. Extraction improved all the isotope ratios measured (lowered % error relative to natural abundances), but interferences were noted for a few samples. The extracted human in-house feces standard was found to have Sn signals reduced by 300-fold, but residual Sn concentrations still interfered with 116Cd, though not 112Cd or 114Cd. Thus, evaluation of the NADDC-extracted in-house fecal standard and reference materials indicate the successful removal of interferences that otherwise prevented accurate determinations of Cd by IDICPMS and show that a number of Cd isotope ratios could be accurately measured (< 1.5% error) for multiple stable isotope tracer studies in a broad range of NaDDC-extracted biological matrixes.  相似文献   

8.
陈祝海 《黄金》2020,41(4):79-82
国家标准方法测定金矿石中的铅、锌、砷、铋、镉和汞需多次溶样,操作繁琐。研究建立了混合酸消解,电感耦合等离子体原子发射光谱法同时测定金矿石中铅、锌、砷、铋、镉和汞的分析方法。实验对混合酸加入量、氟化氢铵溶液加入量、消解温度、消解时间等影响因素进行了优化。该方法各元素加入标准物质回收率为98.0%~104.0%,测定结果的相对标准偏差(n=11)为0.60%~4.76%,且与国家标准方法测定结果一致,具有操作简单,一步消解、多元素同时测定,检测效率高等优点,适用于大批量金矿石样品的检测。  相似文献   

9.
For the analysis of biological and environmental materials by inductively coupled plasma mass spectrometry (ICP-MS), several quantification procedures can be used depending on the precision and accuracy required. Semi-quantitative methods based on the molar response curve were compared with conventional external calibration and standard additions for the analysis of waters and sewage sludges. For the analysis of biological materials, where higher quality data were required, isotope dilution analysis using enriched isotopes was applied. It was observed that the molar sensitivity for different elements in ICP-MS was a simple function of the mass of the isotopes measured after normalization for ionization efficiency which could be fitted to a third-order polynomial equation. Element ionization adjustments for the third-order polynomial, using the Saha equation, allowed the calculation of the plasma ionization temperature and electron density. For the determination of trace metals in waters and sewage sludges, the samples were spiked with different internal standards, ionization corrections were performed and the results obtained agreed with those obtained by external calibration and standard addition within a factor of 2 but, on average, the agreement was within 20%. The determination of molybdenum in biological reference materials was performed by isotope dilution analysis taking into account possible sources of error in the measurements by ICP-MS such as mass discrimination, detector dead time, isobaric interferences and random error propagation.  相似文献   

10.
准确测定道路扬尘样品中重金属元素Cu、Pb、Zn、Cd、Cr、Ni、As,对于城市道路环境污染的防治工作来说意义重大.采用HF-HNO3体系密闭酸溶法消解样品,选择52Cr、60Ni、63Cu、66Zn、75As、111Cd、208Pb为测量同位素,采用He气模式的碰撞反应池技术测定Cr和As,采用仪器自带干扰校正公式...  相似文献   

11.
The determination of trace and ultratrace elements in biological fluids, including urine and serum, by inductively coupled plasma mass spectrometry (ICP-MS) is discussed. Nonspectral interferences and their corrections by external calibration and calibrator addition are discussed in detail. External calibration with internal calibration and dilution is mostly sufficient to correct for encountered biological matrix effects. For some elements, such as Cs and Zn, the use of calibrator addition provides more accurate results. The importance of spectral interferences and their elimination by isotope selection was also studied. Two examples, Cu and Zn, demonstrate the prime importance of selecting an isotope with minimal polyatomic interferences for analysis. By using 65Cu and 68Zn, accurate results for urine and serum can be obtained without excessive pretreatment of samples. Two reference materials, Bio-Rad Lyphochek urine and Kaulson Contox sera, were analyzed. Accuracy was evaluated by comparison with target values, and precision was estimated by the CV within 95% confidence.  相似文献   

12.
使用电感耦合等离子体原子发射光谱法(ICP-AES)直接测定磷矿及磷肥中Cd和Pb,受P和Ca等共存元素的干扰。当待测液中P和Ca的质量浓度分别大于Cd和Pb的10倍时,直接测定Cd、Pb结果的相对误差均大于5%,而磷矿及磷肥中P和Ca相对于Cd和Pb的含量远高于此倍数。研究表明,在pH≈2并含有0.01g/mL抗坏血酸和0.20mol/L KI试液中,强碱性阴离子交换纤维(SBAEF)能够定量萃取试液中的Cd(Ⅱ)和Pb(Ⅱ),而Ca~(2+)、PO_4~(3-)和其他共存的阳离子不被萃取;被SBAEF萃取的Cd(Ⅱ)和Pb(Ⅱ),能够通过0.07mol/L EDTA溶液定量洗脱后,使用ICP-AES测定,从而消除了P和Ca等共存组分对测定的干扰。Cd和Pb的质量浓度分别为1.00×10~(-3)~2.00μg/mL和2.00×10~(-2)~40.0μg/mL时与其发射强度呈线性,线性相关系数R2分别为0.999 294和0.999 984。方法中Cd和Pb的测定下限分别为6.00×10~(-2)和2.00×10-1μg/g。按照实验方法测定模拟样品中Cd和Pb,测定值和理论值相吻合。方法应用于实际磷矿和磷肥样品中Cd和Pb的测定,结果的相对标准偏差(RSD,n=5)不大于4.4%。分离方法也适用于火焰原子吸收光谱法(FAAS)测定磷矿和磷肥中Cd和Pb。  相似文献   

13.
X射线荧光光谱法测定锌精矿中主次量成分   总被引:1,自引:0,他引:1       下载免费PDF全文
采用无水四硼酸锂熔剂熔融法制样,波长色散X射线荧光光谱法测定了锌精矿中的Zn、Pb、Fe、Cu、SiO2、As和Cd等7个主次量成分。采用低温硝酸锂预氧化处理,解决了锌精矿样品对铂黄金坩埚的腐蚀问题。以8个锌精矿标准样品建立校准曲线,用理论α系数法校正基体效应。测定锌精矿样品各成分的相对标准偏差(RSD,n=11)在0.20%~6.8%之间。用标准物质和实际样品验证,测定结果与标准物质认定值和实际样品化学方法测定值相符。  相似文献   

14.
水溶液中痕量金属离子、碘阴离子和亚甲基蓝(C_(16)H_(18)ClN_3·3H_2O,MB)形成疏水性三元缔合物([MI_(n+1)]~-[MB]~+)。通过气体浮选使得复杂基体样品如高盐度工业废水、海水和工业浓硫酸中痕量金属元素(Ag,Cu,Cd,Pb)分离预富集。三元配合物由高纯氮气带入5 mL甲苯溶剂中,甲苯溶液直接应用于火焰原子吸收光谱(FAAS)测定。研究了溶液pH值、KI和MB体积,以及收集试剂种类对分离预富集的影响,并得到了优化操作参数。对含分析物浓度为200 ng/mL的水溶液,其富集  相似文献   

15.
本文以64Zn为内标,以纯锌标准物质作校准曲线,建立了激光剥蚀电感耦合等离子体质谱法(LA-ICP-MS)测定镀锌层中Pb、Cd、As、Sn和Sb的方法。研究了镀锌钢板镀层表面状态和LA的深度分辨率,选择单点剥蚀方式和ICP-MS时间分辨模式采集数据。在优化工作参数基础上,探讨了分馏效应,Pb、Sn的分馏因子接近1,As、Cd、Sb的分馏因子都小于0.8,因而认为Pb、Sn没有分馏效应,As、Cd、Sb存在分馏效应。测定了标准物质和实际样品,测定结果与标称值(ICP-MS测定值)基本相吻合,因而认为该方法是可行的。Pb、Cd、As、Sn和Sb的检出限分别为3、0.3、3、3和0.5 μg/g。  相似文献   

16.
采用电感耦合等离子体原子发射光谱(ICP-AES)法直接测定煤与焦炭中Si,P,Al,V,Cr,Cd,Pb,Cu,Co,Ni,Zn,K,Na,Fe,Ca,Mg,Mn,Ti 18种元素。样品被灰化后取一定量灰样,用氢氧化钠熔融,热水和盐酸浸取,溶液用于测定Si和P,得到煤或焦炭灰中Si,P含量。另取灰化后的全部灰样,用高氯酸和氢氟酸溶解并加热至赶尽高氯酸,用稀硝酸溶解,溶液用于测定Al,V,Cr,Cd,Pb,Cu,Co,Ni,Zn,K,Na,Fe,Ca,Mg,Mn和Ti,得到煤或焦炭中16个元素含量。Si和  相似文献   

17.
针对区域地球化学调查样品,采用HCl-HNO3-HClO4-HF消解样品、王水提取技术,以59Co、60Ni、65Cu、66Zn、114Cd、208Pb作为测定同位素,采用间接经验公式校正质谱干扰,最终实现了电感耦合等离子体质谱法(ICP-MS)同时对Co、Ni、Cu、Zn、Cd和Pb等6种微量元素的测定。详细对比分析了HCl-HNO3-HClO4-HF消解法、王水消解法、微波消解法3种试样处理方法对土壤、水系沉积物和岩石成分分析标准物质的分析数据,结果表明,HCl-HNO3-HClO4-HF消解法和微波消解法的测定值与认定值相符;因微波消解法一次性处理样品数量有限,不适合大批量地质样品分析,故实验选取HCl-HNO3-HClO4-HF法对样品进行溶样。Co、Ni、Cu、Zn、Cd和Pb的校准曲线相关系数均达0.999 9以上,方法检出限(μg/g)分别为:Co 0.04,Ni 0.69,Cu 0.89,Zn 1.31,Cd 0.029,Pb 0.34。将方法应用于土壤、水系沉积物和岩石成分分析标准物质中6种金属元素的测定,结果与认定值基本一致,相对标准偏差(RSD,n=12)均小于8%。方法应用于实际区域地球化学调查样品分析,结果与X射线荧光光谱法(XRF)相吻合。  相似文献   

18.
使用HNO3-HF混合酸体系微波消解煤飞灰样品,建立了电感耦合等离子体质谱法(ICP-MS)测定煤飞灰中14种痕量元素含量的分析方法。样品微波消解的程序为:0.2 g样品中加入10 mL HNO3和5 mL HF,5 min加热到110 ℃保持5 min、5 min升温到150 ℃保持5 min、5 min升至190 ℃恒温30 min。实验对较高浓度元素Be、Co、Cr、Cu、Mn、Mo、Ni、Pb、Sn、V和Zn采取稀释10倍、降低总溶解性固体(TDS)含量后以外标法进行测定,Cd、Sb、Tl等低含量元素则采用标准加入法以消除基体干扰;方法检出限为0.001~0.04 mg/kg。将实验方法应用于煤飞灰标准物质SRM 1633c中11种金属元素(Be、Cd、Co、Cr、Cu、Mn、Ni、Pb、Sb、V、Zn)的测定,结果与认定值基本一致,相对标准偏差(RSD,n=6)为0.3%~3.6%,加标回收率在83%~112%之间。采用实验方法测定煤飞灰实际样品的结果与12个实验室采用电感耦合等离子体原子发射光谱法(ICP-AES)、ICP-MS、原子吸收光谱法(AAS)、X射线荧光光谱法(XRF)和滴定法等其他方法测得结果的平均值对比,经t检验统计表明无显著性差异。  相似文献   

19.
Electrothermal atomic absorption spectrophotometry (ETAAS), inductively coupled plasma mass spectrometry (ICP-MS) and neutron activation analysis (NAA) were used for the quantitative determination of 13 trace elements in urine and seven trace elements in whole blood of healthy unexposed British subjects living in three regions of the United Kingdom. Careful control of pre-analytical and analytical factors have enabled the results obtained from more than 200 individuals to be used in proposing reference intervals for the following elements; Al, As, Cd, Co, Cr, Cu, Hg, Mn, Mo, Ni, Pb, Se, Tl in urine, and Cd, Cr, Hg, Mn, Pb, Se and Tl in blood.  相似文献   

20.
提出了用电感耦合等离子体原子发射光谱法(ICP-AES)同时测定铸铁锅中铝、砷、镉、铬、铅、锑、铊7种对人体有害微量元素的方法。样品用硝酸、盐酸溶解后过滤或样品经硝酸、高氯酸冒烟后用王水溶解,然后选择Al 396.152 nm、As 193.759 nm、Cd 228.802 nm、Cr 267.716 nm、Pb 405.783 nm、Sb 206.833 nm、Tl 351.924 nm作为分析线,用电感耦合等离子体原子发射光谱法(ICP-AES)测定。Fe基体对待测元素的干扰通过在配制校准曲线溶液系列时进行基体匹配和采用干扰系数校正法消除。样品中硅、锰、铜对测定没有干扰。方法的检出限(w/%)为0.000 13(Al)、0.000 32(As)、0.000 03( Cd)、0.000 09(Cr)、0.000 93 (Pb)、0.000 59(Sb)和0.001 2(Tl)。方法应用于铸铁标准物质的分析,测定值与认定值相符;应用于铸铁锅实际样品的分析,回收率在92%~112%之间。  相似文献   

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