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Mihucz V.G.,Eotvos Lorand University | Zaray G.,Hungarian Satellite Trace Elements Institute to UNESCO
Comprehensive Analytical Chemistry | Year: 2016

Given that people may spend more than 90% of their time in enclosed spaces, the investigation of indoor air quality is of paramount importance. Indoor air pollutants such as ozone (O3), nitrogen oxides and volatile organic compounds (VOCs) are linked to outdoor sources. Monoterpenes, such as α-pinene and d-limonene, commonly found indoors have a propensity for oxidation in the air resulting in harmful gaseous products and secondary organic aerosol. Decreased ventilation results in low outdoor air infiltration rates, but the concentration of O3-reactive VOCs increases simultaneously. Chemical compounds in ambient particulate matter (PM) are capable of generating reactive oxygen species causing cellular damage via oxidative stress. Thus, this chapter focuses on sampling strategies for indoor air pollutants and analytical techniques used for their characterisation. Recent advances in terpene oxidation related to indoors is hereby presented. Assessment of oxidative potential of PM and linkage with its constituents are also reviewed. © 2016 Elsevier B.V. Source

Majer Z.,Eotvos Lorand University | Bosze S.,MTA ELTE Research Group of Peptide Chemistry | Szabo I.,MTA ELTE Research Group of Peptide Chemistry | Mihucz V.G.,Eotvos Lorand University | And 9 more authors.
Microchemical Journal | Year: 2015

In vitro antitumor efficacy of several dinuclear bridgings and one chelate structure dirhodium(II) complex of N-protected phenylalanine derivatives were tested on HT-29 cells. The following synthesized and previously characterized complexes were applied in the present work: Rh2(OAc)4-n(O-Phe-Z)n (n=1-4, -O-Phe-Z=N-benzyloxycarbonyl-l-phenylalaninate), Rh2(OAc)4-n(O-Phe-Ac)n (n=1-4, -O-Phe-Ac=N-acetyl-l-phenylalaninate), Rh2(OAc)2(N-Me-D-Phe-O)2 corresponding to N-methyl-d-phenylalaninate as well as Rh2(OAc)4 (-OAc=acetate). Depending on the complex ligand type and its coordination number, the intracellular rhodium (Rh) content determined by total reflection X-ray fluorescence (TXRF) spectrometry in the HT-29 cells varied between 25 and 2500ng/106 cells. In vitro cytotoxicity and cytostatic evaluations of the compounds on HT-29 human cell culture were performed using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium assay. Compared to Rh2(OAc)4, the Rh compounds containing one or two -O-Phe-Z moieties proved to be the most effective on the HT-29 cells. Moreover, synchrotron radiation TXRF-X-ray absorption near edge structure measurements suggested a change of the molecular symmetry of the dirhodium(II) center for the moderately in vitro cytotoxic, lipophilic l-phenylalanine derivative complexes, characterized also by low ligand exchange rate when they were studied on HT-29 cells. © 2015 Elsevier B.V. Source

Mihucz V.G.,Eotvos Lorand University | Mihucz V.G.,Hungarian Satellite Trace Elements Institute to UNESCO | Silversmit G.,Ghent University | Szaloki I.,Budapest University of Technology and Economics | And 10 more authors.
Food Chemistry | Year: 2010

Extraction of As, Cd, Cu, Mn, Ni and Ti from two white as well as from one brown rice samples was studied by inductively coupled plasma sector field mass spectrometry (ICP-SF-MS). Samples were subjected to cold and hot water extraction (rice mass to deionised water volume ratio = 1:6, and 1:3, respectively). The discarded liquids were freeze-dried and digested by microwave-assisted digestion. About 50% of the content of the investigated elements could be extracted from the white rice. In case of the brown rice, the boiling water contained As, Cd, Ni and Ti in significant percentages. Elemental distributions in the rice grains determined by synchrotron radiation confocal micro-X-ray fluorescence analysis revealed that a surface layer having a thickness of about 80 μm is the richest region in elements. Ti was detectable only in this so-called skin region. Good correlation was observed for the extraction of As, Mn, Ni and Ti by the above-mentioned two techniques. Thus, in regions affected by heavy metal and other toxic element contamination, those rice dishes would be preferred whose preparation should need abundant amounts of water for washing and cooking, which later should be discarded. © 2009 Elsevier Ltd. All rights reserved. Source

Szigeti T.,Eotvos Lorand University | Szigeti T.,Hungarian Satellite Trace Elements Institute to UNESCO | Ovari M.,Eotvos Lorand University | Ovari M.,Hungarian Satellite Trace Elements Institute to UNESCO | And 5 more authors.
Science of the Total Environment | Year: 2015

A comprehensive chemical characterization and oxidative potential (OP) assessment of PM2.5 was carried out at an urban site of Budapest between June 2010 and May 2013 to investigate the seasonal variability of particulate phase air pollutants and their oxidative activity. Chemical analyses included the determination of the concentration of trace elements, major water-soluble inorganic ions and carbonaceous fractions (total carbon, water-soluble organic carbon, organic carbon, elemental carbon). The OP of PM2.5 was assessed by antioxidant depletion using a synthetic respiratory tract lining fluid containing ascorbate, reduced glutathione and urate. The mean PM2.5 mass concentration (21.0μgm-3) was just below the 25μgm-3 annual mean PM2.5 limit value set by the European Commission and showed a seasonal pattern with higher levels during winter. On average, 84% of the gravimetric mass could be reconstructed by the chemical measurements. Organic matter and secondary inorganic ions were the most dominant PM2.5 constituents contributing 40 and 29% of its mass, respectively. Changes in the yearly concentrations were not identified for the investigated compounds between 2010 and 2013. Temporal differences in both ascorbate and glutathione oxidation could be observed during the 3-year long sampling period; however, no clear seasonal trend was apparent. OP metrics were associated mainly with traffic-related trace elements; however, other PM sources (i.e., long-range transport, secondary aerosol formation) could also contribute to particulate OP in Budapest. The weak correlation between OP metrics and PM2.5 mass concentration suggests the possibility of using OP as an additional metric in epidemiology. © 2015 Elsevier B.V. Source

Mihucz V.G.,Eotvos Lorand University | Mihucz V.G.,Hungarian Satellite Trace Elements Institute to UNESCO | Zaray G.,Eotvos Lorand University | Zaray G.,Hungarian Satellite Trace Elements Institute to UNESCO
Applied Spectroscopy Reviews | Year: 2016

Interest in studying leaching of toxic (in)organic contaminants such as antimony (Sb) and phthalate esters into drinking water increased because of the ever growing market of water bottled in polyethylene terephthalate (PET) packaging material. Possible contamination sources of drinking water contained in PET bottles are hereby reviewed. Instrumental analytical methods suitable for Sb and phthalate ester determination in drinking water and PET material are also presented. Outcomes on leaching of Sb and phthalate esters into drinking water are grouped according to storage time, exposure to heat/light, sample pH, and PET bottle volume. Methods for estimation of toxicological activity of water in PET bottles are also compiled. Normally, Sb and phthalate ester concentrations in drinking water do not exceed the health limit values in force. Although excellent detection limits can be achieved for phthalate ester determination, due to their ubiquity, results are primarily affected by laboratory cross-contamination. Recent investigations suggest that drinking water stored in PET bottles does not possess either genotoxic or estrogenic activity. © 2016 Taylor & Francis Group, LLC. Source

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