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1.
P. Bartels E. Ebeling B. Kr?mer H. Kruse N. Osius K. Vowinkel O. Wassermann J. Witten C. Zorn 《Fresenius' Journal of Analytical Chemistry》1999,365(5):458-464
During the course of a human biomonitoring project (Biebesheim in Hessen, Germany) we elaborated a simple but sensitive method
for the determination of tri- (TCP), tetra- (TeCP) and pentachlorophenol (PCP) in human urine. Urine samples, spiked with
internal standards, were treated by acid hydrolysis. After a steam bath distillation the distillates were extracted using
solid phase extraction. Derivatization of the chlorophenols was not carried out. GC/ECD system was used for detection. Detection
limits of the chlorophenols were found in the range of 0.02 μg/L urine (detection limits of the ECD: 0.52 to 2.76 μg/L). By
this method mono- and dichlorophenols cannot be detected. We investigated 24h-urine samples of 339 pupils (age 10 to 12 years).
The children live either in the surroundings of a hazardous waste incinerator (SVA) in Biebesheim (n = 193), or controls (i.e.
regions without waste incinerator) in the non polluted areas of Odenwald (n = 90) and Rheintal (n = 56). Between these three
groups we did not find statistically significant differences in chlorophenol concentrations of the urine samples. The 95-percentiles
of the analyzed samples are 0.74 μg/L (2,3,4-TCP), 1.24 μg/L (2,3,5-TCP), 0.70 μg/L (2,3,6–TCP), 1.10 μg/L (2,4,5–TCP), 1.74
μg/L (2,4,6–TCP), 2.84 μg/L (3,4,5–TCP), 4.78 μg/L (2,3,4,5-TeCP), 1.86 μg/L (2,3,4,6-TeCP), 2.90 μg/L (2,3,5,6-TeCP) and
4.39 μg/L (PCP).
Received: 24 February 1999 / Revised: 3 May 1999 / Accepted: 6 May 1999 相似文献
2.
J. Angerer B. Heinzow K. H. Schaller D. Weltle G. Lehnert 《Fresenius' Journal of Analytical Chemistry》1992,342(4-5):433-438
Summary A sensitive, specific and analytically reliable method for the determination of mono-, di-, tri- and tetrachlorophenols in human urine has been elaborated. After acid hydrolysis and a simultaneous steam distillation of the urine samples, spiked with an internal standard, the chromatographically concentrated chlorophenols have been derivatized with pentafluorobenzoylchloride and analyzed by capillary gas chromatography/mass spectrometry. The detection limits for the chlorophenols ranged from 0.2 to 2.5 g/l. Using this method we were able to detect 4-MCP, 2,4-+2,5-DCP, 2,4,6-TCP, 2,4,5-TCP and 2,3,4,6-+2,3,5,6-TeCP in urine samples of a group of 258 men and women which had no known occupational contact to hazardous chemical substances. The 95 percentiles for the concentrations of these substances in the urine samples under investigation were 7.5 (4-MCP); 33.6(2,4-+2,5-DCP); 4,7 (2,4,6-TCP); 4,5 (2,4,5-TCP) and 22.2 (2,3,4,6-+2,3,5,6-TeCP) g per liter. That means, that these chlorophenols are constituents of urine of the normal population in concentrations which in part are greater than that of pentachlorophenol (PCP). 相似文献
3.
A modified headspace liquid-phase microextraction (HS-LPME) method was studied for the extraction of chlorophenols (CPs) from aqueous samples with complicated matrices, before gas chromatographic (GC) analysis with electron capture detection (ECD). Microwave heating was applied to accelerate the evaporation of CPs into the headspace, and an external-cooling system was used to control the sampling temperature. Conditions influencing extraction efficiency, such as the LPME-solvent, the sampling position of LPME, the sampling temperature, microwave power, and irradiation time (the same as sampling time), sample pH, and salt addition were thoroughly optimized. Experimental results indicated that the extraction of CPs from a 10mL aquatic sample (pH 1.0) was achieved with the best efficiency through the use of 1-octanol as solvent, microwave irradiation of 167W, and sampling at 45 degrees C for 10min. The detections were linear in the concentration of 5.0-100microg/L for 2,4-dichlorophenol (2,4-DCP), and 0.5-10microg/L for 2,4,6-trichlorophenol (2,4,6-TCP), 2,3,4,6-tetrachlorophenol (2,3,4,6-TeCP) and pentachlorophenol (PCP). Detection limits were found to be 0.7, 0.04, 0.07, and 0.08microg/L for 2,4-DCP, 2,4,6-TCP, 2,3,4,6-TeCP, and PCP, respectively. A landfill leachate sample was analyzed with recovery between 83 and 102%. The present method was proven to serve as a simple, sensitive, and rapid procedure for CP analysis in an aqueous sample. 相似文献
4.
Jakubowska N Polkowska Z Kujawski W Konieczka P Namieśnik J 《Analytical and bioanalytical chemistry》2007,388(3):691-698
The analysis of volatile organic compounds in samples of biological fluids characterized by complex matrices is highly challenging.
This paper presents a comparison of the results obtained in this field using three solvent-free techniques: thin-layer headspace
with autogenous generation of liquid sorbent (TLHS) and membrane separation of the trace substances (pervaporation, PV), both
of which are coupled to direct aqueous injection gas chromatography–electron capture detection (TLHS–DAI–GC–ECD and PV–DAI–GC–ECD),
as well as conventional static headspace analysis followed by GC analysis with ECD detection (HS–GC–ECD). Basic validation
parameters of the HS–GC–ECD, TLHS–DAI–GC–ECD and PV–DAI–GC–ECD procedures were calculated for water and urine samples. The
calibration curves for all procedures were linear within the concentration range examined. The intermediate precisions of
the procedures were good and reached about 10% (for all analytes) for HS–GC–ECD and TLHS–DAI–GC–ECD. The poorest results were
obtained for PV–DAI–GC–ECD: about 20% for all analytes. The lowest method detection limits were obtained for the TLHS–DAI–GC–ECD
procedure: below 0.0022 μg/L for all analytes. The enrichment factors did not differ significantly between water and urine
samples, indicating little or no matrix effect in all procedures. 相似文献
5.
More than 85% of 10 mg L(-1) of pentachlorophenol (PCP) was removed by magnesium/silver (206/1.47 mM) bimetal system in the presence of acetic acid. Dechlorination was found to be sequential and phenol was identified as the ultimate hydrocarbon skeleton along with some accumulation of tetra-, tri-, and dichlorophenols. The dechlorination reaction was found to follow second-order kinetics. Lower PCP removal efficiency (35%) was observed when the reaction was carried out in the absence of acid using Mg(0)/Ag system. When the reaction was conducted using Mg(0) alone in the presence of acid, substantial sorption of PCP occurred with very low efficiency of PCP dechlorination. Dechlorination studies on 10 mg L(-1) initial concentrations of 2,3,4,6-tetrachlorophenol (2,3,4,6-TeCP) and 2,4,5-trichlorophenol (2,4,5-TCP), under identical conditions as to PCP, revealed that dechlorination efficiency and reaction rate constants decrease with decreasing number of chlorine atoms on the target compound. A correlation (R(2)>0.9) between the dechlorination rate constants and E(LUMO) for chlorophenols was obtained. 相似文献
6.
Kuehnelt D Juresa D Kienzl N Francesconi KA 《Analytical and bioanalytical chemistry》2006,386(7-8):2207-2212
Selenium species were determined using HPLC/ICPMS and HPLC/vapor generation/ICPMS in the urine from seven human volunteers
investigated at background selenium concentrations and at slightly elevated concentrations after ingestion of 200 μg Se as
a selenite supplement. Trimethylselenonium ion (TMSe) was present, together with selenosugars, in the urine samples, a result
that dispels recent doubts about its possible previous misidentification with a cationic selenosugar. Although TMSe was present
as only a trace metabolite in urine from five of the seven volunteers (0.02–0.28 μg Se/L, equivalent to 1–5% of the sum of
selenosugars and TMSe), it was a significant metabolite (up to 4.6 μg Se/L, 22%) in one volunteer, and it was the major identified
metabolite (up to 15 μg Se/L, 53%) in another volunteer. This marked individual variability in the formation of TMSe was maintained
in a duplicate investigation of urine from the same seven volunteers. 相似文献
7.
We have developed a method for measuring 17 sulfonylurea (SU) herbicides in human urine. Urine samples were extracted using
solid phase extraction (SPE), preconcentrated, and analyzed by high-performance liquid chromatography–tandem mass spectrometry
using turboionspray atmospheric pressure ionization. Carbon 13-labeled ethametsulfuron methyl was used as an internal standard.
Chromatographic retention times were under 7 minutes. Total throughput was estimated as >100 samples per day. Because only
one labeled internal standard was available for the analysis, we were forced to reconsider and restructure the validation
process to include stringent stability tests and analyses of urine matrices of differing compositions. We describe our restructured
validation process and the critical evaluation it provides for the method developed. The limits of detection (LOD) ranged
from 0.05 μg/L to 0.10 μg/L with an average LOD of 0.06 μg/L. Average total relative standard deviations were 17%, 12% and
8% at 0.1 μg/L, 3.0 μg/L and 10 μg/L, respectively. Average extraction efficiencies of the SPE cartridges were 87% and 86%
at 2.5 μg/L and 25 μg/L, respectively. Chemical degradation in acetonitrile and urine was monitored over 250 days. Estimated
days for 10% and 50% degradation in urine and acetonitrile ranged from 0.7 days to >318 days. The influence of matrix effects
on precision and accuracy was also explored.
Electronic Supplementary Material Supplementary material is available for this article at
For additional information, contact Anderson Olsson at 相似文献
8.
Migaku Kawaguchi Norihiro Sakui Noriya Okanouchi Koichi Saito 《Analytica chimica acta》2005,533(1):57-65
A new method, stir bar sorptive extraction (SBSE) with in situ derivatization and thermal desorption (TD)-gas chromatography-mass spectrometry (GC-MS), which is used for the determination of trace amounts of chlorophenols, such as 2,4-dichlorophenol (2,4-DCP), 2,4,6-trichlorophenol (2,4,6-TrCP), 2,3,4,6-tetrachlorophenol (2,3,4,6-TeCP) and pentachlorophenol (PCP), in tap water, river water and human urine samples, is described. The derivatization conditions with acetic acid anhydride and the SBSE conditions such as extraction time are investigated. Then, the stir bar is subjected to TD followed by GC-MS. The detection limits of the chlorophenols in tap water, river water and human urine samples are 1-2, 1-2, and 10-20 pg ml−1 (ppt), respectively. The calibration curves for the chlorophenols are linear and have correlation coefficients higher than 0.99. The average recoveries of the chlorophenols in all the samples are higher than 95% (R.S.D. < 10%) with correction using added surrogate standards, 2,4-dichlorophenol-d5, 2,4,6-trichlorophenol-13C6, 2,3,4,6-tetrachlorophenol-13C6 and pentachlorophenol-13C6. This simple, accurate, sensitive and selective analytical method may be applicable to the determination of trace amounts of chlorophenols in liquid samples. 相似文献
9.
Dispersive liquid-liquid microextraction and liquid chromatographic determination of pentachlorophenol in water 总被引:1,自引:0,他引:1
Khalil Farhadi Mir A. Farajzadeh Amir A. Matin Paria Hashemi 《Central European Journal of Chemistry》2009,7(3):369-374
A simple and sensitive dispersive liquid-liquid microextraction method for extraction and preconcentration of pentachlorophenol
(PCP) in water samples is presented. After adjusting the sample pH to 3, extraction was performed in the presence of 1% W/V
sodium chloride by injecting 1 mL acetone as disperser solvent containing 15 μL tetrachloroethylene as extraction solvent.
The proposed DLLME method was followed by HPLC-DAD for determination of PCP. It has good linearity (0.994) with wide linear
dynamic range (0.1–1000 μg L−1) and low detection limit (0.03 μg L−1), which makes it suitable for determination of PCP in water samples.
相似文献
10.
建立浓海水中氯酚的顶空固相微萃取气相色谱法检测方法。采用顶空固相微萃取对海水淡化排放的浓海水样品中2,4,6-三氯酚(2,4,6-TCP)和五氯酚(PCP)进行分离富集,气相色谱-电子捕获检测器(μECD)测定浓海水样品中2,4,6-TCP和PCP的含量。讨论了萃取时间、萃取温度、水样盐度等实验条件对富集效率的影响,确定了萃取时间为40 min,萃取温度为60℃。2,4,6-TCP,PCP的质量浓度在0.500~20.0μg/L范围内与其色谱峰面积呈良好的线性关系,线性相关系数均大于0.999,2,4,6-TCP和PCP的检出限(2S/N)分别为0.055,0.128μg/L,测定结果的相对标准偏差为3.65%~11.4%(n=6),加标回收率为73.5%~119.0%。该方法快速,灵敏度高,适合于浓海水中氯酚的分析。 相似文献
11.
Berthet A Bouchard M Schüpfer P Vernez D Danuser B Huynh CK 《Analytical and bioanalytical chemistry》2011,399(6):2243-2255
Captan and folpet are fungicides largely used in agriculture. They have similar chemical structures, except that folpet has
an aromatic ring unlike captan. Their half-lives in blood are very short, given that they are readily broken down to tetrahydrophthalimide
(THPI) and phthalimide (PI), respectively. Few authors measured these biomarkers in plasma or urine, and analysis was conducted
either by gas chromatography coupled to mass spectrometry or liquid chromatography with UV detection. The objective of this
study was thus to develop simple, sensitive and specific liquid chromatography–atmospheric pressure chemical ionization-tandem
mass spectrometry (LC/APCI-MS/MS) methods to quantify both THPI and PI in human plasma and urine. Briefly, deuterated THPI
was added as an internal standard and purification was performed by solid-phase extraction followed by LC/APCI-MS/MS analysis
in negative ion mode for both compounds. Validation of the methods was conducted using spiked blank plasma and urine samples
at concentrations ranging from 1 to 250 μg/L and 1 to 50 μg/L, respectively, along with samples of volunteers and workers
exposed to captan or folpet. The methods showed a good linearity (R
2 > 0.99), recovery (on average 90% for THPI and 75% for PI), intra- and inter-day precision (RSD, <15%) and accuracy (<20%),
and stability. The limit of detection was 0.58 μg/L in urine and 1.47 μg/L in plasma for THPI and 1.14 and 2.17 μg/L, respectively,
for PI. The described methods proved to be accurate and suitable to determine the toxicokinetics of both metabolites in human
plasma and urine. 相似文献
12.
E. Turiel P. Fernández C. Pérez-Conde A. M. Gutiérrez C. Cámara 《Fresenius' Journal of Analytical Chemistry》1999,365(8):658-662
An atrazine flow-through fluoroimmunosensor was developed, based on an oriented antibody covalently bound to Protein-A (Prot-A)
immobilized on Controlled Pore Glass (CPG). Atrazine was detected “in-situ” by placing the immobilized antibody in the optical
path of the flow cell. Immobilization of 30 μg of polyclonal anti-atrazine antibody on 0.5 g of Prot-A-CPG provided the highest
sensitivity. The effect of several solvents on the covalently immobilized antibodies regeneration was evaluated, the optimum
conditions being achieved by pumping 5% acetonitrile (pH = 3) at 0.15 mL/min for 100 s. The detection limit of the immunosensor
was 0.7 μg/L and the reproducibility was 2% and 4% for 5 μg/L and 40 μg/L, respectively, in the optimum working concentration
range (0.7–50 μg/L). This device allowed 12 samples per hour to be analyzed and had a life-time of 200 assays. Simazine and
desisopropylatrazine (DIA) were not cross-reactive, desethylatrazine (DEA) has a cross-reactivity of 8% and propazine and
prometryn of 44% and 27%, respectively. The immunosensor was applied to the determination of atrazine in tap and ground water
samples spiked at the ?10 and 30 μg/L concentration level.
Received: 30 April 1999 / Revised: 16 July 1999 / Accepted: 21 July 1999 相似文献
13.
J. Feldmann Katie John Paramee Pengprecha 《Analytical and bioanalytical chemistry》2000,368(1):116-121
Cation exchange and anion exchange liquid chromatography were coupled to an ICP-MS and optimised for the separation of 13
different arsenic species in body fluids (arsenite, arsenate, dimethylarsinic acid (DMAA), monomethylarsonic acid (MMAA),
trimethylarsine oxide (TMAO), tetramethylarsonium ion (TMA), arsenobetaine (AsB), arsenocholine (AsC), dimethylarsinoyl ethanol
(DMAE) and four common dimethylarsinoylribosides (arsenosugars). The arsenic species were determined in seaweed extracts and
in the urine and blood serum of seaweed-eating sheep from Northern Scotland. The sheep eat 2–4 kg of seaweed daily which is
washed ashore on the most northern Island of Orkney. The urine, blood and wool of 20 North Ronaldsay sheep and kidney, liver
and muscle from 11 sheep were sampled and analysed for their arsenic species. In addition five Dorset Finn sheep, which lived
entirely on grass, were used as a control group. The sheep have a body burden of approximately 45–90 mg arsenic daily. Since
the metabolism of arsenic species varies with the arsenite and arsenate being the most toxic, and organoarsenic compounds
such as arsenobetaine the least toxic compounds, the determination of the arsenic species in the diet and their body fluids
are important. The major arsenic species in their diet are arsenoribosides. The major metabolite excreted into urine and blood
is DMAA (95 ± 4.1%) with minor amounts of MMAA, riboside X, TMA and an unidentified species. The occurrence of MMAA is assumed
to be a precursor of the exposure to inorganic arsenic, since demethylation of dimethylated or trimethylated organoarsenic
compounds is not known (max. MMAA concentration 259 μg/L). The concentrations in the urine (3179 ± 2667 μg/L) and blood (44
± 19 μg/kg) are at least two orders of magnitude higher than the level of arsenic in the urine of the control sheep or literature
levels of blood for the unexposed sheep. The tissue samples (liver: 292 ± 99 μg/kg, kidney: 565 ± 193 μg/kg, muscle: 680 ±
224 μg/kg) and wool samples (10 470 ± 5690 μg/kg) show elevated levels which are also 100 times higher than the levels for
the unexposed sheep.
Received: 29 February 2000 / Revised: 26 April 2000 / Accepted: 1 May 2000 相似文献
14.
A. Molina-Díaz A. Ruiz-Medina M. L. Fernández-de Córdova 《Fresenius' Journal of Analytical Chemistry》1999,363(1):92-97
A continuous flow-through solid phase spectrophotometric system was developed for the determination of ascorbic acid based
on the measurement of its intrinsic absorbance in the UV region when retained on a 1 mm Sephadex QAE A-25 anion exchanger
gel layer which is placed into an appropriate quartz flow-through cell, the absorbance exhibited by this solid phase being
monitored at 267 nm. A monochannel manifold was used, the sample (300, 600 or 1000 μL) being injected into the carrier solution
(acetate buffer). This solution also elutes the analyte after developing the analytical signal, and regenerates the resin
layer which, therefore, remains ready for the next sample. The linear dynamic range and other analytical parameters vary according
to the sample volume injected. Three calibration lines were established for 300, 600 and 1000 μL sample volume, which ranged
from 1.0 to 20.0, 0.5 to 10.0 and 0.2 to 6.0 μg mL–1, respectively. The detection limits were 0.04 (300 μL), 0.03 (600 μL) and 0.02 μg mL–1 (1000 μL), the sampling rates 28, 24 and 21 h–1, and the RSDs (n = 10) 0.87%, 1.08% and 0.90%, respectively. The amount of ascorbic acid in various samples (pharmaceuticals, sweets and urine)
were successfully determined with this method.
Received: 28 April 1998 / Revised: 3 June 1998 / Accepted: 30 June 1998 相似文献
15.
A. Molina-Díaz A. Ruiz-Medina M. L. Fernández-de Córdova 《Analytical and bioanalytical chemistry》1999,363(1):92-97
A continuous flow-through solid phase spectrophotometric system was developed for the determination of ascorbic acid based
on the measurement of its intrinsic absorbance in the UV region when retained on a 1 mm Sephadex QAE A-25 anion exchanger
gel layer which is placed into an appropriate quartz flow-through cell, the absorbance exhibited by this solid phase being
monitored at 267 nm. A monochannel manifold was used, the sample (300, 600 or 1000 μL) being injected into the carrier solution
(acetate buffer). This solution also elutes the analyte after developing the analytical signal, and regenerates the resin
layer which, therefore, remains ready for the next sample. The linear dynamic range and other analytical parameters vary according
to the sample volume injected. Three calibration lines were established for 300, 600 and 1000 μL sample volume, which ranged
from 1.0 to 20.0, 0.5 to 10.0 and 0.2 to 6.0 μg mL–1, respectively. The detection limits were 0.04 (300 μL), 0.03 (600 μL) and 0.02 μg mL–1 (1000 μL), the sampling rates 28, 24 and 21 h–1, and the RSDs (n = 10) 0.87%, 1.08% and 0.90%, respectively. The amount of ascorbic acid in various samples (pharmaceuticals, sweets and urine)
were successfully determined with this method.
Received: 28 April 1998 / Revised: 3 June 1998 / Accepted: 30 June 1998 相似文献
16.
Summary The determination of selected pesticides and phenols in Portuguese river water samples was carried out from April to September,
1999. The method involved 200 mL samples taken by offline, solid phase extraction by OASIS polymeric cartridges followed by
liquid chromatography-atmospheric pressure, chemical ionization-mass spectrometry (LC-APCI-MS). Recoveries of pesticides were
50–96% and 72–120% for the Platform and HP 1100 instruments, respectively. Chlorophenols gave recoveries of 60–91%. Triazines
and transformation products like desethylatrazine (DEA) and desisopropylatrazine (DIA) and compounds such as diuron and chlorophenols
were positively identified by LC-APCI-MS. The levels detected of the different compounds varied from 0.01–2.61 μg L−1, the most frequently detected compounds being, atrazine, simazine, terbuthylazine, alachlor, metolachlor, Irgarol, diuron,
2,4,6-trichlorophenol, desisopropylatrazine and desethylatrazine. 相似文献
17.
The suitability of 1-nitroso-2-naphthol as a complexing agent for on-line preconcentration of copper using RP-C18 material in a microcolumn with flow injection coupled with flame atomic absorption spectrometry (FI-FAAS) has been tested.
Various parameters affecting complex formation, such as pH, sample flow rate, etc. and its elution into the nebulizer of FAAS
were optimized. ?A 5 × 10–3 mol/L reagent was on-line mixed with aqueous sample solution acidified with 0.1% (v/v) nitric acid ?(pH 3–4) and flowed through
the microcolumn for 30 s. The adsorbed complexes in the microcolumn were eluted with ethanol in 10 s into the nebulizer of
FAAS. A good precision (1.7% for 50 μg/L copper, n = 12), high enrichment factor (19) with detection limit (3σ) 2.0 μg/L,
and sample throughput (90 h–1) were obtained. The method was applied to certified reference materials seawater, mussel (biological), NBS-362 and NBS-364
(special low alloy steel), for the determination of copper, and the results were in good agreement with the certified values.
Received: 4 May 1999 / Revised: 25 June 1999 / Accepted: 29 June 1999 相似文献
18.
M. Reska E. Ochsmann T. Kraus T. Schettgen 《Analytical and bioanalytical chemistry》2010,397(8):3563-3574
Styrene is one of the most important industrial chemicals, with an enormously high production volume worldwide. The urinary
mercapturic acids of its metabolite styrene-7,8-oxide, namely N-acetyl-S-(2-hydroxy-1-phenylethyl)-l-cysteine (PHEMA 1) and N-acetyl-S-(2-hydroxy-2-phenylethyl)-l-cysteine (PHEMA 2), are specific biomarkers for the determination of individual internal exposure to this highly reactive
intermediate of styrene. We have developed and validated a fast, specific and very sensitive method for the accurate determination
of the sum of phenylhydroxyethyl mercapturic acids (PHEMAs) in human urine with an automated multidimensional liquid chromatography–tandem
mass spectrometry method using 13C6-labelled PHEMAs as internal standards. Analytes were stripped from the urinary matrix by online extraction on a restricted
access material, transferred to the analytical column and subsequently determined by tandem mass spectrometry. The limit of
quantification (LOQ) for the sum of PHEMAs was 0.3 μg/L urine and allowed us to quantify the background exposure of the (smoking)
general population. Precision within series and between series ranged from 1.5 to 6.8% at three concentrations ranging from
3 to 30 μg/L urine; the mean accuracy was between 104 and 110%. We applied the method to spot urine samples from 40 subjects
of the general population with no known occupational exposure to styrene. The median levels (range) for the sum of PHEMAs
in urine of non-smokers (n = 22) were less than 0.3 μg/L (less than 0.3 to 1.1 μg/L), whereas in urine of smokers (n = 18), the median levels were 0.46 μg/L (less than 0.3 to 2.8 μg/L). Smokers showed a significantly higher excretion of the
sum of PHEMAs (p = 0.02). Owing to its automation and high sensitivity, our method is well suited for application in occupational or environmental
studies. 相似文献
19.
Minakata K Nozawa H Gonmori K Yamagishi I Suzuki M Hasegawa K Watanabe K Suzuki O 《Analytical and bioanalytical chemistry》2011,400(7):1945-1951
An electrospray ionization tandem mass spectrometric (ESI-MS-MS) method has been developed for the determination of cyanide
(CN–) in blood. Five microliters of blood was hemolyzed with 50 μL of water, then 5 μL of 1 M tetramethylammonium hydroxide solution
was added to raise the pH of the hemolysate and to liberate CN– from methemoglobin. CN– was then reacted with NaAuCl4 to produce dicyanogold, Au(CN)2–, that was extracted with 75 μL of methyl isobutyl ketone. Ten microliters of the extract was injected directly into an ESI-MS-MS
instrument and quantification of CN– was performed by selected reaction monitoring of the product ion CN– at m/z 26, derived from the precursor ion Au(CN)2– at m/z 249. CN– could be measured in the quantification range of 2.60 to 260 μg/L with the limit of detection at 0.56 μg/L in blood. This
method was applied to the analysis of clinical samples and the concentrations of CN– in the blood were as follows: 7.13 ± 2.41 μg/L for six healthy non-smokers, 3.08 ± 1.12 μg/L for six CO gas victims, 730 ± 867 μg
for 21 house fire victims, and 3,030 ± 97 μg/L for a victim who ingested NaCN. The increase of CN– in the blood of a victim who ingested NaN3 was confirmed using MS-MS for the first time, and the concentrations of CN– in the blood, gastric content and urine were 78.5 ± 5.5, 11.8 ± 0.5, and 11.4 ± 0.8 μg/L, respectively. 相似文献
20.
Permethrin is the most popular synthetic pyrethroid insecticide used in agriculture and public health. For the assessment
of human exposure to permethrin, a competitive indirect enzyme-linked immunosorbent assay (ELISA) for the detection of the
glycine conjugate of a major metabolite, cis-/trans-3-(2,2-dichlorovinyl)-2,2-dimethylcyclopropane-1-carboxylic acid (DCCA), of permethrin was developed based on a polyclonal
antibody. An assay based on an antibody with a high sensitivity was optimized and characterized. The IC50 value and the detection range for trans-DCCA–glycine, in the assay buffer were 1.2 and 0.2−7.0 μg/L, respectively. The antibody recognized trans-DCCA–glycine and the mixture of cis-/trans-DCCA–glycine with an isomer range from 30:70 to 50:50 nearly equally. Little or no cross-reactivity to permethrin and its
other free metabolites or glycine conjugates was measured. The integration of the ELISA and solid-phase extraction which was
used to reduce the matrix effect from human urine samples provided for analysis of total cis-/trans-DCCA–glycine at low parts per billion levels in the samples. The limit of quantitation of the target analyte was 1.0 μg/L
in urine with a limit of detection of 0.1 μg/L in buffer. This assay might be a useful tool for monitoring human exposure
to permethrin. 相似文献