Publications by authors named "Pavlina Peikertova"

Road transportation significantly contributes to environmental pollution, both in terms of exhaust and non-exhaust (brake wear) emissions. As was proven, brake wear debris is released in a wide variety of sizes, shapes, and compositions. Although studies confirming the possible adverse health and environmental impact of brake wear debris were published, there is no standardized methodology for their toxicity testing, and most studies focus only on one type of brake pad and/or one test.

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Pharmaceutical products are some of the most serious emergent pollutants in the environment, especially nowadays of the COVID-19 pandemic. In this study, nanogold-composite was prepared, and its catalytic activity for paracetamol degradation was investigated. Moreover, for the first time, recycled waste diatomite earth (WDE) from beer filtration was used for reproducible gold nanoparticle (Au NPs) preparation.

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Although both beryllium and its compounds display high toxicity, little attention has been focused on the removal of beryllium from wastewaters. In this research, magnetically modified biochar obtained from poor-quality wheat with two distinct FeO contents was studied as a sorbent for the elimination of beryllium from an aqueous solution. The determined elimination efficiency was higher than 80% in both prepared composites, and the presence of FeO did not affect the sorption properties.

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Implant surface properties of Ti6Al4V alloy that is currently used as a biocompatible material because of a variety of unique properties can be improved by a self-organized TiO layer. The TiO nanotubes forming on the titanium-based materials is a relatively recent technology for the surface properties modification and represents pronounced potential in promoting cell adhesion, proliferation, and differentiation that facilitate an implant osseointegration. This work focuses on the influence of surface treatment quality and anodic oxidation parameters on the structure features and properties of TiO nanotube coatings.

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Aluminosilicate-based nanocomposites containing multi-layer graphene were prepared from polyaniline/montmorillonite intercalate in two different forms: tablets and thin layers. Starting materials, polyaniline/montmorillonite powder and polyaniline/montmorillonite layers deposited on quartz glass, were prepared by polymerization of aniline in presence of montmorillonite particles. Powder was compacted into tablets using pressure 400 MPa.

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Article Synopsis
  • Settled road dust is composed of a mix of natural and human-made particles, which can negatively affect the environment and atmosphere when resuspended.
  • Researchers studied the heavy metal content of road dust in both a high-traffic urban area and a low-traffic suburban area in Ostrava, Czech Republic, by collecting monthly dust samples from March to October 2015.
  • The study revealed significant differences in heavy metal levels, with most pollutants in urban areas being linked to vehicle traffic, while only iron content varied significantly by month.
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Glibenclamide, a drug used for the treatment of type 2 diabetes, belongs to Class II of Biopharmaceutical Classification System. It is a highly permeable, but poorly water-soluble drug. Nanoparticles of glibenclamide were prepared by an emulsion solvent evaporation method using dichloromethane as a solvent of glibenclamide and 3% (w/w) aqueous solution of carboxymethyl dextran sodium salt as a stabilizer, which was found as optimal.

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Physical and chemical methods for nanoparticle synthesis are disadvantageous to less energy demanding and more efficient and environmentally friendly biological approaches. Thus, in this paper, we designed simple, bottom-up, , static experiment under laboratory conditions using suspension of mixed flower pollen grains for nanoparticle synthesis. Pollen grains provided template substrates for gold nanoparticles synthesis from dissolved Au(III).

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Wear debris from automotive brake systems represents a major source of non-exhaust emissions from road traffic and its production increases with number of cars worldwide. However, impact of brake wear debris on the environment and organisms is still not clear. One of the most possible ways by which these particles may affect living organisms is oxidative stress.

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Photoactive and non-hazardous kaolinite/ZnO nanocomposite with 50 wt.% of ZnO nanoparticles was prepared using simple and cheap hydrothermal method. The resulting solid phase was separated by decantation, and dried at 105 °C.

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Most of drugs are only slightly soluble in the circulatory system of the human body. This reduces the efficiency of their use and that is why new ways how to increase their solubility are investigated. One way to improve the solubility of the drug is to reduce its particle size.

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Hydroxyapatite is one of the building blocks of hard tissues of living organisms. Therefore stability of nanoparticles in experimental solutions of different pH similar to one in human body is important issue for precise tailoring of the synthesis of hydroxyapatite particles on clay mineral substrate. In this study, the stability (amount of Ca and P released into the water) of calcium deficient hydroxyapatite/clay mineral nanocomposites was investigated.

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Organically modified vermiculites can be used as nanostructured adsorbents of organic compounds from waters or gaseous phases similarly as organically modified smectites or bentonites. There is a large amount of research data focused on adsorption properties of organoclays, however only a little information is about their post-sorption treatment. This work is focused on study of two possible ways of subsequent processing of organovermiculite after its use as sorbent for heavily polluted waste water.

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Metal based particles were detected in pulmonary tumor tissue samples and reference lung tissue samples (lung tissue without carcinoma) by Raman microspectroscopy and scanning electron microscopy. Many of these particles were in the size below 1 m. Using scanning electron microscopy, particles based on iron were found in the majority of samples.

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Wear particles from automotive friction brake pads of various sizes, morphology, and chemical composition are significant contributors towards particulate matter. Knowledge concerning the potential adverse effects following inhalation exposure to brake wear debris is limited. Our aim was, therefore, to generate brake wear particles released from commercial low-metallic and non-asbestos organic automotive brake pads used in mid-size passenger cars by a full-scale brake dynamometer with an environmental chamber simulating urban driving and to deduce their potential hazard in vitro.

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Nanoparticles can be considered as a useful tool for improving properties of poorly soluble active ingredients. Hydrochlorothiazide (Class IV of the Biopharmaceutical Classification System) was chosen as a model compound. Antisolvent precipitation-solvent evaporation and emulsion solvent evaporation methods were used for preparation of 18 samples containing hydrochlorothiazide nanoparticles.

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Single and multilayer TiO₂ thin films coated on two types of soda-lime glass substrates (microscope slides and cylinders) were prepared by a chelating agent-assisted sol-gel method, using ethyl acetoacetate as a chelating agent, dip-coating and calcination at 500 °C for 2 h in air. Phase composition, microstructural, morphological and optical properties of thin films were comprehensively investigated by using XRF, advanced XRD analysis, Raman and UV-vis spectroscopy and AFM. It was found out that the thickness of thin films increases linearly with increasing number of deposited layers, indicating a good adhesion of the titania solution to a glass substrate as well as to a previously calcined layer.

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Motor vehicle exhaust and non-exhaust processes play a significant role in environmental pollution, as they are a source of the finest particulate matter. Emissions from non-exhaust processes include wear-products of brakes, tires, automotive hardware, road surface, and traffic signs, but still are paid little attention to. Automotive friction composites for brake pads are composite materials which may consist of potentially hazardous materials and there is a lack of information regarding the potential influence of the brake wear debris (BWD) on the environment, especially on human health.

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Article Synopsis
  • The paper investigates the creation and properties of graphite/TiO2 nanocomposites aimed at fighting bacterial infections.
  • Multiple ratios of TiO2 nanoparticles were combined with graphite through thermal hydrolysis and characterized using advanced techniques like X-ray powder diffraction and microscopy.
  • The antibacterial effectiveness was tested against several bacterial strains, showing significant activity, especially against P. aeruginosa after exposure to light for 180 minutes.
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This paper describes laboratory preparation, characterization and antibacterial activity testing of ZnO/kaoline composites. ZnO/kaoline composites with 50 wt.% of ZnO were laboratory prepared, dried at 105 °C and calcined at 500 °C.

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One approach for the enhancement of oral drug bioavailability is the technique of nanoparticle preparation. Risedronate sodium (Biopharmaceutical Classification System Class III) was chosen as a model compound with high water solubility and low intestinal permeability. Eighteen samples of risedronate sodium were prepared by the solvent evaporation technique with sodium dodecyl sulfate, polysorbate, macrogol, sodium carboxymethyl cellulose and sodium carboxymethyl dextran as nanoparticle stabilizers applied in three concentrations.

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The paper addresses laboratory preparation and antibacterial activity testing of kaolinite/nanoTiO2 composite in respect of the daylight irradiation time. Kaolinite/nanoTiO2 composites with 20 and 40 wt% of TiO2 were laboratory prepared, dried at 105 °C and calcined at 600 °C. The calcination caused transformation of kaolinite to metakaolinite and origination of the metakaolinite/nanoTiO2 composite.

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Background: Nanotechnology is receiving enormous funding. Very little however is known about the health dangers of this technology so far. Chronic tonsillitis is one of a number of diseases called idiopathic.

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This study aimed to evaluate the palatine tonsils of patients with chronic tonsillitis and spinocellular carcinoma to determine the presence of nano-sized particles. Tonsil samples from adult patients with chronic tonsillitis and spinocellular carcinoma of the palatine tonsil were dried and analyzed using a scanning electron microscope with the X-ray microprobe of an energy-dispersive spectroscope. Demographic data and smoking histories were obtained.

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