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Surface modification of nanoparticles for sustaining sensitivity of surface-enhanced raman spectrometric measurements in salinated environment
Týčová, Anna; Přikryl, Jan; Vaňhara, P.; Klepárník, Karel; Foret, František
2020 - anglický
Surface-enhanced Raman spectrometry (SERS) represents a powerful method for analysis of a broad spectrum of analytes ranging from inorganic ions to biomolecules of high complexity. It combines the potential\nof Raman spectrometry for a definite identification of an analyte with remarkable sensitivity achieved by the surface enhancement effect occurring on metal nanoparticles. While low ionic strength influences positively\nthe sensitivity of the SERS measurement, a higher level of inorganic salts leads to fast ruining of colloidal character, which completely devastates the effect of the surface enhancement. The common stabilization of\nnanoparticles by a layer of polymers has a negative impact on the SERS sensitivity since it shields the nanoparticle surface from the analytes. In this work, we aim at the development of the bi-ligand system of\nnanoparticles surface modification for improved stability of colloid in saline solution at sustaining the potential for sensitive SERS analyses. The proposed system relies on the binding of 3-mercaptopropionic acid and\nthiolated polyethylene glycol in a suitable ratio onto the nanoparticle surfaces. While the short chains of the acid sustain the accessibility of the surface for analytes, the polymeric structures act as a steric barrier\npreventing colloid aggregation.
Klíčová slova:
bi-ligand; nanoparticle; saline solution; surface-enhanced Raman spectrometry
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Surface modification of nanoparticles for sustaining sensitivity of surface-enhanced raman spectrometric measurements in salinated environment
Surface-enhanced Raman spectrometry (SERS) represents a powerful method for analysis of a broad spectrum of analytes ranging from inorganic ions to biomolecules of high complexity. It combines the ...
Photochemical vapour generation of bismuth coupled with atomic fluorescence spectrometry
Štádlerová, Barbora; Vyhnanovský, Jaromír; Dědina, Jiří; Musil, Stanislav
2020 - anglický
Atomization of bismuthane in the flame-in-gas-shield atomizer by photochemical vapour generation coupled with atomic fluorescence spectrometry.
Klíčová slova:
atomic fluorescence spectrometry; bismuth; photochemical vapour generation
Plné texty jsou dostupné v digitálním repozitáři Akademie Věd.
Photochemical vapour generation of bismuth coupled with atomic fluorescence spectrometry
Atomization of bismuthane in the flame-in-gas-shield atomizer by photochemical vapour generation coupled with atomic fluorescence spectrometry.
DNA damage induced by occupational exposure to copper oxide nanoparticles
Rössner st., Pavel; Pelcová, D.; Elzeinová, Fatima; Mikuška, Pavel; Večeřa, Zbyněk; Coufalík, Pavel; Vlčková, Š.; Fenclová, Z.; Rössnerová, Andrea
2020 - anglický
Copper oxide nanoparticles (CuO NPs) have a widespread use in industry, chemistry, in production of electronic devices and as an antimicrobial agent. Although copper is an important biogenic element, CuO NPs are toxic with the ability to induce oxidative stress, apoptosis, cell cycle arrest or DNA damage. For humans, the inhalation route is the most common way of exposure to CuO NPs. In the body, CuO NPs may be either deposited in the lungs, or transported to other organs. Their presence usually causes oxidative stress or inflammatory responses, consequently leading to DNA damage. In this study, we investigated the effect of CuO NPs inhalation on DNA damage in a group of researches conducting animal exposure experiments. The subjects were exposed to various metal oxide nanoparticles, including CuO NPs, by inhalation for an average of 4.9 ± 0.4 years. The average mass concentration of Cu in the air during the experiment was 7.3 ± 3.2 ng/m3. Subjects not exposed to nanoparticles served as a control group. We applied micronucleus assay using Human Pan Centromeric probes to detect DNA damage and to distinguish between the frequency of centromere positive (CEN+) and centromere negative (CEN−) micronuclei (MN) in the binucleated cells. We\ndid not find differences between both groups for either mean MN frequency (10.38 ± 2.50 vs. 11.88 ± 3.01 MN/1000 binucleated cells), or CEN+/CEN- ratio (58%/42% vs. 55%/45%), for the exposed and controls, respectively. In conclusion, inhalation of CuO NPs at this low-level exposure had no effect on chromosomal losses and/or breaks.
Klíčová slova:
copper oxide nanoparticles; inhalation; DNA damage
Plné texty jsou dostupné v digitálním repozitáři Akademie Věd.
DNA damage induced by occupational exposure to copper oxide nanoparticles
Copper oxide nanoparticles (CuO NPs) have a widespread use in industry, chemistry, in production of electronic devices and as an antimicrobial agent. Although copper is an important biogenic element, ...
Deposition of dried colloidal suspension via nanoelectrospray
Jonas, Vladimír; Týčová, Anna; Přikryl, Jan; Kotzianová, A.; Velebný, V.; Foret, František
2020 - anglický
Electrospray is a relatively well-established tool for the deposition of nanoparticles. In this work, we use nanoelectrospray (nES) operating at flow rates down to tens of nanoliters per minute. As a result, the formed aerosol consists of very small droplets quickly drying during the flight towards a counter-electrode. Therefore, we obtained deposits of increased homogeneous distribution without an undesirable coffee-ring effect. Moreover, the character of the aerosol plume is only a few millimeters wide, so it allows good control over the deposit localization.
Klíčová slova:
nanoparticles; nanoelectrospray; silver
Dokument je dostupný na externích webových stránkách.
Deposition of dried colloidal suspension via nanoelectrospray
Electrospray is a relatively well-established tool for the deposition of nanoparticles. In this work, we use nanoelectrospray (nES) operating at flow rates down to tens of nanoliters per minute. As a ...
Chemical vapor generation of cadmium for analytical atomic spectrometry
Sagapova, Linda; Kodríková, Barbora; Svoboda, Milan; Musil, Stanislav; Kratzer, Jan
2020 - anglický
Chemical vapor generation of cadmium volatile compounds was optimized, several reaction modifiers based on inorganic salts and complexes of CrIII+, CoII+, TiIII+, TiIV+ were tested. Their use resulted in 4-5 times enhancement in sensitivity, reflected also in corresponding increase of generation efficiency and better repeatability. Generation efficiency was determined from a comparison between sensitivities obtained with chemical vapor generation and conventional solution nebulization, both simultaneously coupled with inductively coupled plasma mass spectrometry. The identity of the generated cadmium compounds was identified.
Klíčová slova:
cadmium; chemical vapor generation; atomic absorption spectrometry
Plné texty jsou dostupné v digitálním repozitáři Akademie Věd.
Chemical vapor generation of cadmium for analytical atomic spectrometry
Chemical vapor generation of cadmium volatile compounds was optimized, several reaction modifiers based on inorganic salts and complexes of CrIII+, CoII+, TiIII+, TiIV+ were tested. Their use resulted ...
Effect of metal sensitizers on photochemical vapor generation of bismuth for analytical atomic spectrometry
Vyhnanovský, Jaromír; Yildiz, D.; Musil, Stanislav
2019 - anglický
Three new sensitizers with a significant positive effect on the photochemical vapor generation of bismuth were described. Cobalt was found to be the most effective and led to a significant enhancement of the signal.
Klíčová slova:
photochemical volatile species generation; bismuth; AAS
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Effect of metal sensitizers on photochemical vapor generation of bismuth for analytical atomic spectrometry
Three new sensitizers with a significant positive effect on the photochemical vapor generation of bismuth were described. Cobalt was found to be the most effective and led to a significant enhancement ...
Metals in atmospheric particulate matter
Barboříková, H.; Mikuška, Pavel; Hegrová, J.; Pokorná, Petra; Krajčovič, J.
2019 - anglický
Atmospheric pollution is one of the most serious global enviroment problem. Metals constitute important class of pollutants which have received athe attention of researchers all over the world. Metals have strong potential to be adsorbed on particulate matter and than enter the human body through inhalation causing several health issue (asthma, lung cancer).
Klíčová slova:
aerosol; metals
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Metals in atmospheric particulate matter
Atmospheric pollution is one of the most serious global enviroment problem. Metals constitute important class of pollutants which have received athe attention of researchers all over the world. Metals ...
Atomization of bismuthane in two flame atomizers for atomic fluorescence spectrometry
Štádlerová, Barbora; Kolrosová, Marta; Dědina, Jiří; Musil, Stanislav
2019 - anglický
Atomization of bismuthane in the minature diffusion flame and the flame-in-gas-shield atomizer by hydride generation coupled with atomic fluorescence spectrometry.
Klíčová slova:
atomic fluorescence spectrometry; bismuth; hydride generation
Plné texty jsou dostupné na jednotlivých ústavech Akademie věd ČR.
Atomization of bismuthane in two flame atomizers for atomic fluorescence spectrometry
Atomization of bismuthane in the minature diffusion flame and the flame-in-gas-shield atomizer by hydride generation coupled with atomic fluorescence spectrometry.
On-line simultaneous determination of ammonia/ammonium in ambient air
Čapka, Lukáš; Mikuška, Pavel
2019 - anglický
Presented paper describes methods for on-line determination of gaseous ammonia and particulate ammonium in ambient air.
Klíčová slova:
ammonia; ammonium; CGU-ACTJU sampler
Plné texty jsou dostupné v digitálním repozitáři Akademie Věd.
On-line simultaneous determination of ammonia/ammonium in ambient air
Presented paper describes methods for on-line determination of gaseous ammonia and particulate ammonium in ambient air.
LIBS assessment of spatial photon-upconversion nanoparticle distribution in model plants (R. sativus and L. minor)
Modlitbová, P.; Novotný, K.; Hlaváček, Antonín; Pořízka, P.; Kaiser, J.
2019 - anglický
In the present study, radish (Raphanus sativus L.) and common duckweed (Lemna minor L.) were treated with an aqueous dispersion of carboxylated silica-coated photon-upconversion nanoparticles containing rare-earth elements (Y, Yb, and Er). The total content of rare earths and their bioaccumulation factors were determined in the root, hypocotyl, and leaves of R. sativus after 72 hours, and in L. minor fronds after 168 hours. In R. sativus, translocation factors were determined as the ratio of rare earths content in hypocotyl versus roots and in leaves versus hypocotyl. The lengths of the root and hypocotyl in R. sativus, as well as the frond area in L. minor were monitored as toxicity end points. To distinguish rare-earth bioaccumulation patterns, two-dimensional maps of elemental distribution in the whole R. sativus plant and in L. minor fronds were obtained by using laser-induced breakdown spectroscopy with a lateral resolution of 100 μm. Obtained results revealed that the tested nanoparticles became adsorbed on L. minor fronds and R. sativus roots, and got transferred from roots through the hypocotyl into leaves in R. sativus. Our results show that bioaccumulation patterns and spatial distribution of rare earths in nanoparticle-treated plants differ from those of positive control (the mixture of YCl3, YbCl3, and ErCl3).
Klíčová slova:
photonupconversion nanoparticles; luminescent nanomaterials; bioaccumulation
Plné texty jsou dostupné v digitálním repozitáři Akademie Věd.
LIBS assessment of spatial photon-upconversion nanoparticle distribution in model plants (R. sativus and L. minor)
In the present study, radish (Raphanus sativus L.) and common duckweed (Lemna minor L.) were treated with an aqueous dispersion of carboxylated silica-coated photon-upconversion nanoparticles ...
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