Abstract：
BACKGROUND:Lead is an environmental pollutant, and human exposure is assessed by monitoring lead concentrations in blood. Because the main source of environmental exposure has been the use of leaded gasoline, its phase-out has led to decreased lead concentrations in the general population. Therefore, validated analytical methods for the determination of lower lead concentrations in blood (<150 microg/L) are needed. In addition, new ISO standards require that laboratories determine and specify the uncertainty of their results. METHODS:We validated a method to determine lead in blood at concentrations up to 150 microg/L by electrothermal atomic absorption spectrometry with Zeeman background correction according to EURACHEM guidelines. Blood samples were diluted (1:1 by volume) with 2 mL/L Triton X-100. NH4H2PO4 (5 g/L) and Mg(NO3)2 (0.5 g/L) were used as modifiers. Matrix-matched standards were used for calibration. RESULTS:We determined the limits of detection (3.1 microg/L) and quantification (9.4 microg/L). Repeatability and intermediate imprecision within the range 35-150 microg/L were <5.5% and <6.0%, respectively. We assessed trueness by use of certified reference materials, by recovery tests, and by comparison with target values of other reference materials (candidate external quality assessment samples). The expanded uncertainty ranged from 20% to 16% (with a confidence level of 95%) depending on concentration. CONCLUSIONS:This study provides a working example of the estimate of uncertainty from method performance data according to the EURACHEM/CITAC guidelines. The estimated uncertainty is compatible with quality specifications for the analysis of lead in blood adopted in the US and the European Union.
journal_name
Clin Chemjournal_title
Clinical chemistryauthors
Patriarca M,Castelli M,Corsetti F,Menditto Adoi
10.1373/clinchem.2003.029223subject
Has Abstractpub_date
2004-08-01 00:00:00pages
1396-405issue
8eissn
0009-9147issn
1530-8561pii
clinchem.2003.029223journal_volume
50pub_type
杂志文章abstract：BACKGROUND:The current diagnosis and monitoring of bladder cancer are heavily reliant on cystoscopy, an invasive and costly procedure. Previous efforts in urine-based detection of bladder cancer focused on targeted approaches that are predicated on the tumor expressing specific aberrations. We aimed to noninvasively de...
journal_title：Clinical chemistry
pub_type： 杂志文章
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更新日期：2019-07-01 00:00:00
abstract：:Adrenocortical causes of hypertension are established by examining the mineralocorticoid hormones produced in the zona glomerulosa and zona fasciculata. In the zona glomerulosa, aldosterone excess leads to hypertension, hypokalemia, and suppressed plasma renin activity, with increased concentrations of urinary aldoste...
journal_title：Clinical chemistry
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doi：
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doi：10.1373/clinchem.2004.032292
更新日期：2004-05-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：1978-02-01 00:00:00
abstract：:We compared cyclosporine concentrations in whole blood as measured by HPLC and by RIA with a monoclonal antibody specific for cyclosporine with 3H- or 125I-labeled cyclosporine ligand. The 3H-RIA kit slightly underestimated cyclosporine concentrations (greater than 600 micrograms/L) in comparison with HPLC. Over a wid...
journal_title：Clinical chemistry
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doi：
更新日期：1989-01-01 00:00:00
abstract：BACKGROUND:The recent discovery of the presence of circulating cell-free fetal DNA in maternal plasma opens up new prenatal diagnostic applications and provides new avenues for clinical investigation. It is of research and potential diagnostic interest to determine whether fetal trisomy 21 may be associated with quanti...
journal_title：Clinical chemistry
pub_type： 临床试验,杂志文章,多中心研究
doi：
更新日期：1999-10-01 00:00:00
abstract：:We report the presence of complexes between aspartate aminotransferase (AST, EC 2.6.1.1) and immunoglobulin (Ig) in the serum of a patient suffering from lung cancer with metastasis to the liver. After fractionation of the serum by gel filtration, AST-Ig complexes (AST-IgA, AST-IgG) were demonstrated by counterimmunoe...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1983-02-01 00:00:00
abstract：:We describe a process for preparing a cholesterol-rich lipoprotein extract from bovine serum. The material is used to enhance cholestrol concentration up to 3.5 g/liter in a clear control material from human serum. The optical clarity of the enriched serum is only slightly affected by lyophilization and reconstitution...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1976-08-01 00:00:00
abstract：:Brain proteins extractable with distilled water or 9 mol/L urea were subjected to two-dimensional gel electrophoresis. They are examined in relation to the identification of actin, tubulin, neurofilament proteins, glial fibrillary acidic protein; proteins of human embryonic neocortex, synaptosomes, myelin, and plasma;...
journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1982-04-01 00:00:00
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更新日期：2014-04-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：1994-09-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：1978-01-01 00:00:00
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doi：
更新日期：2002-11-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：1990-06-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：1990-12-01 00:00:00
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journal_title：Clinical chemistry
pub_type： 杂志文章
doi：
更新日期：1980-05-01 00:00:00
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doi：
更新日期：1992-04-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：1999-09-01 00:00:00
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journal_title：Clinical chemistry
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doi：
更新日期：2001-03-01 00:00:00
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pub_type： 杂志文章
doi：10.1373/49.7.1050
更新日期：2003-07-01 00:00:00
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doi：
更新日期：2002-06-01 00:00:00
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doi：
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doi：
更新日期：1979-04-01 00:00:00
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doi：
更新日期：1994-07-01 00:00:00
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doi：
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doi：
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journal_title：Clinical chemistry
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doi：
更新日期：1989-08-01 00:00:00
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doi：
更新日期：1977-07-01 00:00:00
