共查询到20条相似文献,搜索用时 31 毫秒
1.
Mei-Wo Yii Zal U’yun Wan Mahmood 《Journal of Radioanalytical and Nuclear Chemistry》2011,289(3):819-833
This study with sampling expeditions of marine sediment, seawater and biota were performed at 30 stations within Malaysian
Exclusive Economic Zone (EEZ). A total of >400 samples were collected to determine the activity concentration of anthropogenic
radionuclides (239+240Pu, 137Cs) and their activity ratio (239+240Pu/137Cs) in sediments, seawater and biota. The purpose of this study was to determine the concentration levels for these radionuclides
and to evaluate any occurrence of radioactive contamination. Sediment cores were obtained using multicorer device, while water
samples via co-precipitation techniques and biota was purchased from local fishermen. The activity concentrations of 239+240Pu in sediment, seawater and biota were ranged 0.21–0.45 Bq/kg dry wt., 2.33–7.95 mBq/m3 and <0.008 Bq/kg fresh wt., respectively. Meanwhile, the values of 137Cs were ranged <1.00–2.71 Bq/kg dry wt. in sediment, 3.40–5.89 Bq/m3 in seawater and <0.05–0.41 Bq/kg fresh wt. in biota, respectively. Activity ratios of 239+240Pu to 137Cs obtained seem to confirm that these artificial radioactivities were mainly due to global nuclear fallout. 相似文献
2.
M. Buzoianu 《Accreditation and quality assurance》2003,8(3-4):124-129
A lot of effort is being made in Romania to meet the present main strategic goal – EU integration. Since the confidence in
measurements is of considerable importance in almost every field of activity, the National Institute of Metrology (INM) is
involved in improving its calibration and measurement capabilities to provide services in accordance with the latest European
Regulation.
Within this framework the assurance of the required traceability of all measurements plays a most important role. As reliable
analytical measurements depend largely upon reference materials and the assurance of the traceability of amount measurements
is still developing in Romania, a new approach regarding the function of Certified Reference Materials (CRMs) may be emphasized.
The experience of the INM as well as new developments in Romania in preparation and certification of Reference Materials (RMs)
are described. A short review of the locally available RMs and CRMs is given. Some aspects regarding the use of RMs and CRMs,
especially for calibration, are discussed for their applicability for analytical measurements.
Received: 31 October 2002 Accepted: 24 January 2003
Presented at CERMM-3, Central European Reference Materials and Measurements Conference: The function of reference materials
in the measurement process, May 30–June 1, 2002, Rogaška Slatina, Slovenia
Correspondence to M. Buzoianu 相似文献
3.
M. Feinberg Michel Montamat Cédric Rivier Béatrice Lalère Guillaume Labarraque 《Accreditation and quality assurance》2002,7(10):403-408
The expression of measurement uncertainty in analytical chemistry still presents some difficulties. According to the various
guides and standards, several approaches are possible. This paper present two referenced approaches applied to the determination
of Pb in a biological tissue at the mg kg–1 level. Estimations were achieved, either from inter-laboratory precision data, or from the uncertainty propagation equation
applied to the measurements of a single laboratory. When comparing final values, for an average concentration of about 2.0
mg kg–1, expanded uncertainties range from ±0.05 mg kg–1 up to ±0.31 mg kg–1, i.e. by a factor of 6. Obviously, both approaches of estimating uncertainty do not cover the same sources of uncertainty
and it is interesting to try to understand better these discrepancies in order to try to define realistic guidelines for analysts.
Moreover the experimental results of the study are given where a wide number of techniques is applied.
Received: 5 May 2002 Accepted: 17 June 2002
Correspondence to M. Feinberg 相似文献
4.
Aguinaga N Campillo N Viñas P Hernández-Córdoba M 《Analytical and bioanalytical chemistry》2008,391(4):1419-1424
This paper describes a headspace solid-phase microextraction (HS-SPME) procedure coupled to gas chromatography with mass spectrometric
detection (GC–MS) for the determination of eight PAHs in aquatic species. The influence of various parameters on the PAH extraction
efficiency was carefully examined. At 75 °C and for an extraction time of 60 min, a polydimethylsiloxane–divinylbenzene (PDMS/DVB)
fiber coating was found to be most suitable. Under the optimized conditions, detection limits ranged from 8 to 450 pg g−1, depending on the compound and the sample matrix. The repeatability varied between 7 and 15% (RSD). Accuracy was tested using
the NIST SRM 1974b reference material. The method was successfully applied to different samples, and the studied PAHs were
detected in several of the samples.
Figure Headspace SPME sampling followed by GC–MS facilitates routine monitoring of PAHs in aquatic species 相似文献
5.
Certified reference material for quantification of polycyclic aromatic hydrocarbons in sediment from the National Metrology Institute of Japan 总被引:2,自引:0,他引:2
Nobuyasu Itoh Yoshie Aoyagi Akiko Takatsu Takashi Yarita 《Analytical and bioanalytical chemistry》2009,393(8):2039-2049
The National Metrology Institute of Japan has issued a certified reference material (CRM) of freshwater lake sediment for
polycyclic aromatic hydrocarbon (PAHs) analyses. The certification used three extraction techniques: pressurized liquid extraction
(PLE) with toluene, PLE with dichloromethane/ethyl acetate (1:1 by volume), and alkaline extraction (1 M KOH in methanol)
in combination with microwave-assisted extraction. Both gas chromatography/mass spectrometry (GC/MS) and liquid chromatography/dopant-assisted
atmospheric pressure photoionization/MS (LC/DA-APPI/MS) analyses were used. Certified values are provided for 18 PAHs at 1–25 μg
kg−1 except for perylene (2.08 × 103 μg kg−1), and information values are provided for two. Since the values of PAHs in the CRM are much lower than those in other CRMs
and are comparable to those found at sites with little human influence, the CRM is suitable for PAH monitoring in sediment
and soil samples. 相似文献
6.
Inagaki K Takatsu A Watanabe T Aoyagi Y Yarita T Okamoto K Chiba K 《Analytical and bioanalytical chemistry》2007,387(7):2325-2334
A new marine sediment certified reference material, NMIJ CRM 7306-a, for butyltin and phenyltin analysis has been prepared
and certified by the National Metrological Institute of Japan at the National Institute of Advanced Industrial Science and
Technology (NMIJ/AIST). Candidate sediment material was collected at a bay near industrial activity in Japan. After air-drying,
sieving, and mixing the material was sterilized with γ-ray irradiation. The material was re-mixed and packaged into 250 glass
bottles (15 g each) and these were stored in a freezer at −30 °C. Certification was performed by use of three different types
of species-specific isotope-dilution mass spectrometry (SSID–MS)—SSID–GC–ICP–MS, SSID–GC–MS, and SSID–LC–ICP–MS, with 118Sn-enriched organotin compounds synthesized from 118Sn-enriched metal used as a spike. The 118Sn-enriched mono-butyltin (MBT), dibutyltin (DBT), and tributyltin (TBT) were synthesized as a mixture whereas the 118Sn-enriched di-phenyltin (DPhT) and triphenyltin (TPhT) were synthesized individually. Four different extraction methods,
mechanical shaking, ultrasonic, microwave-assisted, and pressurized liquid extraction, were adopted to avoid possible analytical
bias caused by non-quantitative extraction and degradation or inter-conversion of analytes in sample preparations. Tropolone
was used as chelating agent in all the extraction methods. Certified values are given for TBT 44±3 μg kg−1 as Sn, DBT 51 ± 2 μg kg−1 as Sn, MBT 67 ± 3 μg kg−1 as Sn, TPhT 6.9 ± 1.2 μg kg−1 as Sn, and DPhT 3.4 ± 1.2 μg kg−1 as Sn. These levels are lower than in other sediment CRMs currently available for analysis of organotin compounds. 相似文献
7.
Using Plackett-Burman experimental design the parameters of different ways of sampling (design and materials of the sampling
mold, conditions of solidification of samples) that influence on the homogeneity of copper-titanium-zinc alloy samples in
the production of titanium zinc were determined.
Based on these results, the homogeneity of samples taken with two different sampling molds was investigated with GD-OES technique
regarding alloyed elements (Cu and Ti) and impurities (Fe, Pb, Cd, Sn, Al) and was evaluated with analysis of variance (ANOVA).
For Cu, Ti and Fe an overall (combined) uncertainty for different sampling approaches were estimated and compared to the expanded
uncertainty evaluated without including the uncertainty due to sampling.
Received: 28 October 2002 Accepted: 2 January 2003
Presented at CERMM-3, Central European Reference Materials and Measurements Conference: The function of reference materials
in the measurement process, May 30–June 1, 2002, Rogaška Slatina, Slovenia
Correspondence to B. Kokliˇc 相似文献
8.
C. Giachetti 《Chromatographia》1998,48(5-6):443-449
Summary Low amounts of triethanolamine, collected in ORBO 53 tubes during air sampling, required the development of a very sensitive
method for determination. After desorption and silylation reaction with trimethylsilyl imidazole/trimethyl chlorosilane, the
derivative was analyzed by gas chromatography-mass spectrometry on an Ultra 2 silica capillary column in single ion monitoring
mode (retention time: about 6 min). The method has a detection limit of 1–2 pg with a desorption efficiency of about 81%.
Linearity of response was ascertained in the ranges 10–100 ng and 100–1000 ng. Short-term method validation was carried out
by intra- and inter-day assays on three amounts for each reference calibration curve. All results satisfied the pre-defined
acceptance criteria. In general, the whole procedure was easily performed and was appropriate for our needs. Breakthrough
volume was appropriate for our needs. Breakthrough volume was determined on authentic samples and was about 40–60 L, using
a flow rate of 1 L·min−1. The amounts of triethanolamine found in the samples ranged from 150 to 250 ng (about 2.5–4.2 μg·m−3). 相似文献
9.
Results of a thorough study and application of flow injection atomic absorption spectrometry for the determination of As,
Pb and Hg in parts per million to sub-parts per billion levels in environmental and biological samples have been described.
Various standard reference materials from the National Bureau of Standards, USA, the National Institute of Standards and Technology,
USA, the Community Bureau of Reference, Brussels, Belgium and the National Institute for Environmental Studies, Japan and
Standard Chinese river sediment were used. By flow injection hydride generation AAS the standard reference materials were
analyzed for As and Pb. Mercury was determined by cold vapour flow injection AAS from environmental and biological standard
reference materials. The technique is fast, simple and highly sensitive. It takes only 30 s for each analysis from the digested
solution. The detection limits of As, Pb and Hg are 1.8 μg L–1 and 2.0 μg L–1 and 1.5 μg L–1, respectively. The results show good agreement with the certified values.
Received: 9 May 1996 / Revised: 13 August 1996 / Accepted: 14 August 1996 相似文献
10.
I. Šperlingová L. Dabrowská V. Stránský J. Kuˇcera M. Tichý 《Accreditation and quality assurance》2003,8(3-4):113-116
A preliminary batch of the reference material was prepared by freeze-drying pooled urine samples obtained from healthy persons
occupationally exposed to styrene. Tests for homogeneity and stability were performed by determining urine concentrations
of mandelic (MA) and phenylglyoxylic acids (PGA). The urinary MA and PGA concentrations were followed over an 8-month period
using high performance liquid chromatography (HPLC). No changes of the concentration values were found. Pure PA and PGA from
Merck and Fluka, respectively, were used for traceability purposes, because certified or standard reference materials for
MA and PGA do not exist. Control material ClinChek-Urine Control (Recipe) was analysed simultaneously. The mean values of
MA and PGA compared well with the means of control samples and fell within the control range. The certified values and their
uncertainties were evaluated from the results of interlaboratory comparisons, homogeneity (277.0 ± 7.4 mg L−1 for MA and 148.0 ± 4.7 mg L−1 for FGA) and stability tests. The values are unweighted arithmetical averages of accepted results and their uncertainties
are combined uncertainties enlarged by coefficient k=1, evaluated from the standard uncertainties of the interlaboratory comparison, homogeneity and stability tests.
Received: 17 September 2002 Accepted: 1 November 2002
Acknowledgement This work was supported by the Internal Grant Agency of Ministry of Health of the Czech Republic (Grant NJ/6784–3).
Presented at CERMM-3, Central European Reference Materials and Measurements Conference: The function of reference materials
in the measurement process, May 30–June 1, 2002, Rogaška Slatina, Slovenia
Correspondence to I. Šperlingová 相似文献
11.
Inagaki K Kuroiwa T Narukawa T Yarita T Takatsu A Okamoto K Chiba K 《Analytical and bioanalytical chemistry》2008,391(6):2047-2054
A new cod fish tissue certified reference material, NMIJ CRM 7402-a, for methylmercury analysis was certified by the National
Metrological Institute of Japan in the National Institute of Advanced Industrial Science and Technology (NMIJ/AIST). Cod fish
was collected from the sea close to Japan. The cod muscle was powdered by freeze-pulverization and was placed into 600 glass
bottles (10 g each), which were sterilized with γ-ray irradiation. The certification was carried out using species-specific
isotope dilution gas chromatography inductively coupled plasma mass spectrometry (SSID–GC–ICPMS), where 202Hg-enriched methylmercury (MeHg) was used as the spike compound. In order to avoid any possible analytical biases caused by
nonquantitative extraction, degradation and/or formation of MeHg in sample preparations, two different extraction methods
(KOH/methanol and HCl/methanol extractions) were performed, and one of these extraction methods utilized two different derivatization
methods (ethylation and phenylation). A double ID method was adopted to minimize the uncertainty arising from the analyses.
In order to ensure not only the reliability of the analytical results but also traceability to SI units, the standard solution
of MeHg used for the reverse-ID was prepared from high-purity MeHg chloride and was carefully assayed as follows: the total
mercury was determined by ID–ICPMS following aqua regia digestion, and the ratio of Hg as MeHg to the total Hg content was
estimated by GC–ICPMS. The certified value given for MeHg is 0.58 ± 0.02 mg kg−1 as Hg.
Figure NMIJ CRM 7402-a: cod fish tissue for MeHg analysis 相似文献
12.
M. Paneli E. Rosenberg M. Grasserbauer M. Ceulemans F. Adams 《Analytical and bioanalytical chemistry》1997,357(6):756-762
In order to evaluate the effectiveness of recent restrictions of Austrian government for the consumption of leaded gasoline,
ionic organolead species were determined in 13 sampling sites of the Austrian and Slovakian Danube-basin in 4 bimonthyl sampling
campaigns. Speciation analysis was performed using a rapid and sensitive method based on Grignard derivatization of the ionic
organolead species and a GC-MIP-AED coupling for separation and detection. The operational variables were optimized for chromatographic
resolution and detection limits. 100 ml of sample were used for the analyses and the detection limits for trimethyllead were
0.5 ng Pb l–1 and for triethyllead 0.85 ng Pb l–1. In general, absence of organolead induced pollution has been observed for most of the sampling locations and campaigns.
Only the part of the river Danube between Vienna (Austria) and Bratislava (Slovakia), which is loaded by various intensive
anthropogenic sources, showed in two campaigns the occurrence of very low trimethyl- and triethyllead concentrations, ranging
between 1.2–12.0 ng Pb l–1 and 1.6–5.8 ng Pb l–1, respectively.
Received: 21 March 1996 / Revised: 6 May 1996 / Accepted: 9 May 1996 相似文献
13.
A method was developed for sampling and selective quantitative determination of typical volatile organic compounds (VOCs)
in ambient urban air. A mobile and self-contained dual-channel air sampling tool based on solid phase adsorption was constructed.
A simple calibration procedure circumventing the adsorption/desorption process was designed. The method was validated for
seven “key-analytes”: n-hexane, 3-methyl-2-pentene, benzene, tetrachloroethene, styrene, 1,2,4-trimethylbenzene and acetophenone.
The complete air sampling equipment is easily accommodated in a business suitcase. The lower limits of the practical working
ranges are between 0.1 μg m–3 (tetrachloroethene) and 1.2 μg m–3 (benzene). Air samples were collected at a location in Salzburg with heavy motor vehicle traffic and measured in order to
prove a satisfactory method performance under practical monitoring conditions.
Received: 4 January 1998 / Revised: 14 September 1998 / Accepted: 21 October 相似文献
14.
C. Galas Umberto Sansone Maria Belli Sabrina Barbizzi Philippe Cyffroy Giovanni Paolo Fanzutti Volodya Kanivets Rita Ocone Raffaella Piani Milena Repetti Michele Riccardi Cinzia Terzoni Oleg V. Voitsekhovitch 《Accreditation and quality assurance》2002,7(5):202-208
Sampling and sample preparation/processing are known to carry large, but typically unknown uncertainty contribution to the
final analytical data and there is a lack of qualitative and quantitative data on the comparability of results achieved by
the different sampling methods.
To this end, an intercomparison programme was founded by the European Commission, in which different institutions participated
using their own ”in-situ” methods (”ANPA”, ”EDF” and ”MIDIYA”) for collection of water and suspended material in freshwater
bodies. The main criterion for this intercomparison was the agreement among the 137Cs activity concentrations in the dissolved phase (Bq l–1), those associated with the suspended particles (Bq g–1) and the concentrations of total suspended material (TSM) in the water body (mg l–1). The results show that the sampling systems provide TSM concentration results with low accuracy; on the contrary, they are
recommended for the determination of 137Cs activity concentration in the dissolved phase. Concerning the determination of radiocaesium activity concentration in the
suspended particles, the ”EDF” system provides the more reliable results.
Received: 10 December 2001 Accepted: 4 March 2002 相似文献
15.
Ultrasonic slurry sampling electrothermal vaporization dynamic reaction cell inductively coupled plasma mass spectrometry
(USS–ETV–DRC–ICP–MS) for the determination of Cr, Cd and Pb in several plastic samples, using NH4NO3 as the modifier, is described. The influences of the instrumental operating conditions and the slurry preparation technique
on the ion signals are investigated. A reduction in the intensity of the background at signals corresponding to chromium masses
(arising from matrix elements) was achieved by using NH3 as the reaction cell gas in the DRC. The method was applied to determine Cr, Cd and Pb in two polystyrene (PS) samples and
a polyvinyl chloride (PVC) sample using two different calibration methods, namely standard addition and isotope dilution.
The results were in good agreement with those for digested samples analyzed by ultrasonic nebulization DRC–ICP–MS. The precision
between sample replicates was better than 17% with the USS–ETV–DRC–ICP–MS method. The method detection limits, estimated from
standard addition curves, were about 6–9, 1–2 and 8–11 ng g−1 for Cr, Cd and Pb, respectively, in the original plastic samples. 相似文献
16.
Oddvar R?yset 《Fresenius' Journal of Analytical Chemistry》1998,360(1):69-73
Three different methods for sampling and determination of nitrogen dioxide in urban air are compared: an NO/NOx-monitor and an active (pumped) and a passive sampling method. For the latter two methods, sodium iodide is used as absorbent.
For weekly averages the results from the passive sampler are within 10–20% of the results for the two other methods in the
concentration range 15–30 μg NO2/m3. The detection limit for the passive sampler is 1 μg NO2/m3 (7 days), the precision is 5% and the accuracy is estimated to 20%. The active iodide method agrees very well with the NO/NOx-monitor. Compared on 24 h basis for a period of 3 months, covering a concentration range of 5–45 μg NO2/m3, the deviation between the two methods is within 5%, and the absorption capacity of the iodide reagent is excellent as the
breakthrough is below 1%.
Received: 3 December 1996 / Revised: 11 March 1997 / Accepted: 15 March 1997 相似文献
17.
R. Schindler R. Vonach B. Lendl R. Kellner 《Fresenius' Journal of Analytical Chemistry》1998,362(1):130-136
A new process control methodology for the simultaneous determination of sugars, alcohols and organic acids in wine based
on multivariate evaluation of mid-IR transmission spectra of wine samples is presented. In addition to ethanol several lower
level wine components (glucose, fructose, glycerol, citric-, tartaric-, malic-, lactic- and acetic acid) were determined.
To establish a multivariate calibration model a set of 72 calibration solutions was prepared and measured, using a novel,
fully automated sequential injection (SI) system with Fourier transform infrared (FTIR) detection. The resulting spectra were
evaluated using a partial least square (PLS) model. The developed PLS model was then applied to the analysis of real wine
samples containing 79–91 g L–1 ethanol, 5.9–8.1 g L–1 glycerol, 0.4–6.9 g L–1 glucose, 1.5–7.5 g L–1 fructose, 0.3–1.6 g L–1 citric acid, 1.0–1.7 g L–1 tartaric acid, 0.02–3.2 g L–1 malic acid, 0.4–2.8 g L–1 lactic acid and 0.15–0.60 g L–1 acetic acid, yielding results which were in good agreement with those obtained by an external reference method (HPLC-IR).
The short analysis time (less than 3 min) together with high reproducibility makes the newly developed method applicable to
process control and screening purposes (average of the standard deviations calculated from four repetitive measurements of
six different real samples: ethanol: 0.55 g L–1, glycerol: 0.037 g L–1, glucose: 0.056 g L–1, fructose: 0.036 g L–1, citric acid: 0.020 g L–1, tartaric acid: 0.010 g L–1, malic acid: 0.052 g L–1, lactic acid: 0.012 g L–1 and acetic acid: 0.026 g L–1).
Received: 21 January 1998 / Revised: 5 March 1998 / Accepted: 6 March 1998 相似文献
18.
Snow crab is a major fishery in the North Atlantic region. During crab processing the proteins are aerosolized and some are
responsible for development of occupational asthma. Tropomyosin and arginine kinase have recently been reported as major snow
crab allergens. A liquid chromatographic tandem mass spectrometric method has been developed for simultaneous analysis of
these two proteins in air samples collected from processing plants. These proteins were initially isolated then characterized
by use of mass spectrometry to determine their primary structure and signature peptides. The signature peptides were chemically
synthesized in light and heavy forms and used as standards for developing the multiple-reaction monitoring transitions to
monitor allergen levels. A validation study was performed; precision and accuracy were 1.8–8% and 91–104%, respectively. Replicate
air samples were collected on air filters from two crab-processing plants in Newfoundland and Labrador (NL) and four located
in Quebec. In NL, measured levels of both tropomyosin and arginine kinase were between 1 and 20 ng m−3. In Quebec plants, however, levels were found to be much higher at 2–2400 ng m−3. Significant differences were also observed among the plants and individual processing workstations. For the first time arginine
kinase has been detected in its aerosolized form in processing plants. In general, levels of the allergens were highest in
the butchering and cooking areas; plant design can, however, have a significant effect on levels of the allergens. 相似文献
19.
Staimer N Delfino RJ Bufalino C Fine PM Sioutas C Kleinman MT 《Analytical and bioanalytical chemistry》2005,383(6):955-962
A personalized, miniaturized air sampling system was evaluated to estimate the daily exposure of pediatric asthmatics to nitrogen
dioxide (NO2). The lightweight device (170 g) uses a sampling pump connected to a solid sorbent tube containing triethanolamine (TEA)-impregnated
molecular sieve. The pump is powered by a 9 V battery and samples air over a 24 h period at a collection rate of 0.100 L/min.
After exposure, the solid sorbent is removed from the tubes for spectrophotometric analysis (Griess Assay). The lower detection
limit of the overall method for NO2 is 11 μg/m3. The linearity, precision and accuracy of the sampler was evaluated. Different NO2 concentrations generated in the laboratory (range: 50 to 340 μg/m3) were simultaneously measured by the TEA tube samplers and colocated continuous chemiluminescent NOx analyzers (reference method). The coefficient of determination for the laboratory test derived from ordinary linear regression
(OLR) was r
2=0.99 (y
OLR=0.94x−4.58) and the precision 3.6%. Further, ambient NO2 concentrations in the field (range: 10–120 μg/m3) were verified with continuous chemiluminescent monitors next to the active samplers. Reweighted least squares analysis (RLS)
based on the least median squares procedure (LMS) resulted in a correlation of r
2=0.68 for a field comparison in Riverside, CA (y
RLS=1.01x−0.94) and r
2=0.92 in Los Angeles, CA (y
RLS=1.31x−7.12). The precision of the TEA tube devices was 7.4% (at 20–60 μg/m3 NO2) under outdoor conditions. Data show that the performance of this small active sampling system was satisfactory for measuring
environmental concentrations of NO2 under laboratory and field conditions. It is useful for personal monitoring of NO2 in environmental epidemiology studies where daily measurements are desired. 相似文献
20.
Narukawa T Chiba K Kuroiwa T Yarita T Takatsu A 《Analytical and bioanalytical chemistry》2007,389(2):661-666
An arsenobetaine [(CH3)3As+CH2COO−] solution reference material, NMIJ CRM 7901-a, intended for use in the speciation of arsenic compounds, was developed and
certified by the National Metrology Institute of Japan (NMIJ), part of the National Institute of Advanced Industrial Science
and Technology (AIST). The high-purity arsenobetaine powder was synthesized from trimethylarsine [(CH3)3As], and it was dissolved in water in order to prepare 20 mg kg−1 of arsenobetaine standard solution. The solution was bottled in 500 bottles (each containing 10 ml). Certification of the
CRM for arsenobetaine was conducted by NMIJ. The concentration of As was determined by four independent analytical techniques
(ICP–MS, ICP–OES, GFAAS and LC–ICP–MS), and each result was converted to the arsenobetaine concentration by applying an appropriate
factor. The arsenobetaine concentration in the CRM was thus certified. 相似文献