Mercury detection
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Cell wall envelopes treated with sodium hydroxide and spray-dried were used as mercury sorbents. The sorbent having sorption capacity 17.7 ± 0.1 μmol/g determined was employed for preconcentration of mercury containing 1-10 ng/L. After preconcentration, bioavailable mercury was detected in samples of soil, stream, and tap water via induction of bioluminescence of E. coli ARL1. Iron and manganese at concentrations of tenth microgram per liter interfered bioluminescence detection of mercury. In tap water was detected semiquantitatively 0.127 ± 0.1 nmol/L by the induction of bioluminescence of E. coli ARL1 in medium with tryptone after preconcentration using a method of standard addition.
- MeSH
- elektrochemie metody MeSH
- finanční podpora výzkumu jako téma MeSH
- metalothionein analýza chemie MeSH
- Publikační typ
- přehledy MeSH
Industrial expansion in the North Bohemian Coal District over the past decades has had an adverse effect not only on stream sediments but also on the freshwater system. So far mercury occurrence has not been properly investigated in the area. In response to this situation, the present study applies mercury quantification and speciation in order to predict the possible mobility of mercury. The enrichment factor (EF) and sediment quality guidelines (SQGs) were used to calculate the degree of mercury contamination. An automatic mercury analyser was employed to detect the total mercury content (Hg-T) and Thermal Desorption technique was used to identify mercury species. All the sediment samples were assessed with the contamination degree which increased to very severe in stream sediments in the middle section of the river course. Mercury species identified were chiefly the insoluble forms Hg-FeS2 and HgS. Lignite components and combustion residues were identified as the primary source of Hg contamination in the area.
- MeSH
- chemické látky znečišťující vodu analýza chemie MeSH
- geologické sedimenty chemie MeSH
- monitorování životního prostředí metody MeSH
- řeky MeSH
- rtuť chemie MeSH
- uhlí MeSH
- Publikační typ
- časopisecké články MeSH
- Geografické názvy
- Česká republika MeSH
CE methods for the speciation of inorganic and organomercury compounds are reviewed. Sample preparation, separation conditions and detection modes are discussed. Efficient separation and sensitive determination of mercury species by CE typically involves complexation with various thiols, chromogenic and other chelating agents; however, some methods do not require complexation. Spectrophotometric detection based on UV-visible absorption is by far the most commonly used. Hyphenated techniques, such as CE/inductively coupled plasma (ICP)-MS, hydride generation coupled to ICP-MS or atomic fluorescence spectrometry and CE/atomic absorption spectrometry are gaining popularity due to their high sensitivity and selectivity. Last, but not least, the potential and applications of electrochemical methods for detection of separated mercury species are outlined.
The aim of this survey was to compare total mercury (THg) in canned fish in terms of species and fishing area. A number of 110 samples of canned fish, which were divided by fish species and fishing area, were analysed. The highest THg content in muscle tissue was found in the escolar. In other fish species, the highest level was detected in tuna. Mercury content in tuna differed significantly from mackerel, sardine, and sprat. Mercury content in herring differed significantly from sprat. The order of the fish according to their THg content corresponds to their status in the aquatic food chain. A significant difference was also found between fish caught from the closed Mediterranean and Black Sea and fish caught in the open oceans. In terms of THg content, the results of this study indicate good quality of various species of canned fish caught in worldwide locations.
- MeSH
- druhová specificita MeSH
- hodnocení rizik MeSH
- oceány a moře MeSH
- potrava z moře (živočišná) analýza MeSH
- potraviny konzervované analýza MeSH
- rtuť analýza MeSH
- ryby * MeSH
- svaly chemie MeSH
- tuňák MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- srovnávací studie MeSH
- Geografické názvy
- Černé moře MeSH
- Česká republika MeSH
- oceány a moře MeSH
- Středozemní moře MeSH
Highly stable, small-sized and evenly distributed solid mercury nanoparticles capped with ibuprofen (Ibu-HgNPs) were prepared via reduction with hydrazine and capped with ibuprofen as a stabilizing agent. Characterization of Ibu-HgNPs was carried out by UV-Vis spectrophotometry and transmission electron microscopy (TEM). The prepared Ibu-HgNPs were immobilized onto a glassy carbon electrode (GCE) and used for the first time as the sensing element for voltammetric determination of low concentrations of acrylamide (AA) in aqueous solutions. Various parameters such as the type of supporting electrolyte, voltammetric mode, frequency, deposition time, stirring rate and initial potential were optimized to obtain the highest peak current of AA. The sensor delivered the best results in combination with the square wave voltammetry (SWV) mode, with good repeatability (relative standard deviation (RSD) of 25 repetitions was 1.4% for 1000 ppb AA). The study further revealed that Ibu-HgNPs are strongly adhered to GCE and hence do not contaminate the environment even after several runs. The newly developed AA sensor provides linear calibration dependence in the range of 100-1300 ppb with an R2 value of 0.996 and limit of detection (LOD) of 8.5 ppb. Negligible interference was confirmed from several organic compounds, cations and anions. The developed sensor was successfully applied for AA determination in various types of environmental real water samples to prove its practical usefulness and applicability.
- MeSH
- akrylamid MeSH
- elektrochemické techniky MeSH
- elektrody MeSH
- ibuprofen MeSH
- nanočástice * MeSH
- rtuť * MeSH
- Publikační typ
- časopisecké články MeSH
OBJECTIVE: Mercury dental amalgam restorations are an important source of chronic exposure to mercury in the whole population and special attention should be paid not only to occupational exposure to mercury during the preparation and administration of amalgam. The authors' report is an up-to-date contribution to the health risk assessment of mercury use in dentistry, namely occupational exposure to mercury in dentists working with dental amalgam and exposure to mercury in persons treated with amalgam dental restorations. METHODS: Determination of total mercury in samples of biological material (urine, hair) was performed during 2017 and 2018 in 50 persons by the AAS method using the mercury vapour generation technique at 254.6 nm. RESULTS: Current dental exposures based on the most recent findings do not exceed acceptable risk levels and are below the biological limit of mercury in urine valid for occupationally exposed persons (100 μg.g-1 of creatinine), namely median value was 1.48 (min. < limit of detection (LOD), max. 17.14) μg.g-1 of creatinine (40 persons), total mercury content in hair of dental personnel expressed as median value was 0.340 (min. 0.060, max.1.628) μg.g-1. In controls (10 persons) was total mercury content in urine expressed as median value 0.36 (min. < LOD, max. 2.74) μg.g-1 of creatinine, in hair was median value 0.224 (min. 0.059, max. 0.453) μg.g-1. CONCLUSIONS: Authors support opinion that amalgam fillings in the oral cavity are a permanent source of mercury for the body itself.
- MeSH
- hodnocení rizik MeSH
- lidé MeSH
- pracovní expozice analýza škodlivé účinky MeSH
- rtuť analýza moč škodlivé účinky MeSH
- vlasy, chlupy chemie MeSH
- vystavení vlivu životního prostředí analýza škodlivé účinky MeSH
- zubní amalgam škodlivé účinky MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
In this paper, we present an electrochemical DNA-protein interaction assay based on a combination of protein-specific immunoprecipitation at magnetic beads (MBIP) with application of oligonucleotide (ON) probes labeled with an electroactive oxoosmium complex (Os,bipy). We show that double-stranded ONs bearing a dT20 tail labeled with Os,bipy are specifically recognized by the tumor suppressor p53 protein according to the presence or absence of a specific binding site (p53CON) in the double-stranded segment. We demonstrate the applicability of the Os,bipy-labeled probes in titration as well as competition MBIP assays to evaluate p53 relative affinity to various sequence-specific or structurally distinct unlabeled DNA substrates upon modulation of the p53-DNA binding by monoclonal antibodies used for the immunoprecipitation. To detect the p53-bound osmium-labeled probes, we took advantage of a catalytic peak yielded by Os,bipy-modified DNA at the mercury-based electrodes, allowing facile determination of subnanogram quantities of the labeled oligonucleotides. Versatility of the electrochemical MBIP technique and its general applicability in studies of any DNA-binding protein is discussed.
- MeSH
- DNA chemie MeSH
- elektrochemické techniky přístrojové vybavení metody MeSH
- elektrody MeSH
- katalýza MeSH
- lidé MeSH
- nádorový supresorový protein p53 chemie MeSH
- oligonukleotidové sondy chemie MeSH
- osmium chemie MeSH
- rtuť chemie MeSH
- vazba proteinů MeSH
- vodík chemie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
- práce podpořená grantem MeSH
The developed method for mercury speciation analysis has been validated and used for the biomonitoring study of mercury species in human hair. Statistical evaluation proved the reliability of simplified determination of inorganic mercury (difference between total mercury and methylmercury). The results of the validation showed that the method is very well suitable for the determination of both species of mercury in hair for biomonitoring purposes. Non-exposed schoolchildren from three areas in the western and central part of the Czech Republic were chosen as the target group. Tenth of a microgram per gram of the total mercury were generally found in the analyzed hair; values higher than 1 microg g(-1) were detected only exceptionally. Comparable results were obtained for two western areas and differed significantly from those for the third area located in the central part of the Czech Republic. In the areas examined, the mean methylmercury contents amounted to 23-46% of the total mercury in the hair. The results confirm an assumption that exposure to mercury does not pose a significant risk to the population in the Czech Republic.
- MeSH
- lidé MeSH
- methylortuťné sloučeniny analýza MeSH
- mladiství MeSH
- monitorování životního prostředí metody normy MeSH
- rtuť analýza MeSH
- senzitivita a specificita MeSH
- vlasy, chlupy chemie metabolismus MeSH
- Check Tag
- lidé MeSH
- mladiství MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Geografické názvy
- Česká republika MeSH
