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Gruiz K.,Budapest University of Technology and Economics | Molnar M.,Budapest University of Technology and Economics | Fenyvesi E.,Cyclolab Cyclodextrin R and D Laboratory Ltd
Construction for a Sustainable Environment - Proceedings of the International Conference of Construction for a Sustainable Environment | Year: 2010

Within the frame of Hungarian MOKKA project a comprehensive and uniform remediation technology-verification system was developed and applied which facilitates better understanding and evaluation of the remediation technologies and is able to increase trust in remediation, including in situ biotechnologies. The feasibility of the MOKKA multistage technology-verification system has been demonstrated in three innovative in situ remediation cases in Hungary. The comprehensive verification system was applied to the detailed characterisation and evaluation of an in situ complex cyclodextrin-enhanced remediation technology (CDT). The cyclodextrin-enhanced bioremediation is an innovative remediation technology developed and used for soil contaminated with hydrocarbons of limited bioavailability. The feasibility of the CDT was demonstrated in the field and the developed innovative tools for the verification of the technology proved the efficiency and the competitiveness of the technology. © 2010 Taylor & Francis Group, London.

Nagy Z.M.,Budapest University of Technology and Economics | Molnar M.,Budapest University of Technology and Economics | Fekete-Kertesz I.,Budapest University of Technology and Economics | Molnar-Perl I.,Eötvös Loránd University | And 2 more authors.
Science of the Total Environment | Year: 2014

Small scale laboratory experiment series were performed to study the suitability of a cyclodextrin-based sorbent (ß-cyclodextrin bead polymer, BCDP) for modelling the removal of micropollutants from drinking water and purified waste water using simulated inflow test solutions containing target analytes (ibuprofen, naproxen, ketoprofen, bisphenol-A, diclofenac, β-estradiol, ethinylestradiol, estriol, cholesterol at 2-6. μg/L level). This work was focused on the preliminary evaluation of BCDP as a sorbent in two different model systems (filtration and fluidization) applied for risk reduction of emerging micropollutants.For comparison different filter systems combined with various sorbents (commercial filter and activated carbon) were applied and evaluated in the filtration experiment series.The spiked test solution (inflow) and the treated outflows were characterized by an integrated methodology including chemical analytical methods gas chromatography-tandem mass spectrometry (GC-MS/MS) and various environmental toxicity tests to determine the efficiency and selectivity of the applied sorbents.Under experimental conditions the cyclodextrin-based filters used for purification of drinking water in most cases were able to absorb more than 90% of the bisphenol-A and of the estrogenic compounds. Both the analytical chemistry and toxicity results showed efficient elimination of these pollutants. Especially the toxicity of the filtrate decreased considerably.Laboratory experiment modelling post-purification of waste water was also performed applying fluidization technology by ß-cyclodextrin bead polymer. The BCDP removed efficiently from the spiked test solution most of the micropollutants, especially the bisphenol-A (94%) and the hormones (87-99%). The results confirmed that the BCDP-containing sorbents provide a good solution to water quality problems and they are able to decrease the load and risk posed by micropollutants to the water systems. © 2014 Elsevier B.V.

Gruiz K.,Budapest University of Technology and Economics | Molnar M.,Budapest University of Technology and Economics | Fenyvesi E.,Cyclolab Cyclodextrin RandD Laboratory Ltd. | Hajdu Cs.,Budapest University of Technology and Economics | And 2 more authors.
Journal of Inclusion Phenomena and Macrocyclic Chemistry | Year: 2011

Experimental results, which may serve as basis for innovative applications of cyclodextrins (CDs) in environmental technologies, are presented here. Some newly developed CD-aided tools are used in sampling, measuring the concentration or testing the effect of contaminants in water and soil. The innovative methods such as the bacterial bioassays with CD-increased sensitivity or the CD-filled absorptive samplers for air and water sampling are utilised in environmental exposure, hazard and risk assessment. Technological developments aim the reduction of the risk of chemical substances in waters and soils. CD-aided environmental remediation is introduced through examples for the elimination of organic contaminants from water by CD-filters, and for the enhancement of the mobility and availability of soil contaminants in this way increasing the efficiency of soil remediation by water extraction, chemical oxidation, biodegradation, etc. © 2010 Springer Science+Business Media B.V.

Hajdu C.,Budapest University of Technology and Economics | Gruiz K.,Budapest University of Technology and Economics | Fenyvesi E.,Cyclolab Cyclodextrin RandD Laboratory Ltd | Nagy Z.M.,Budapest University of Technology and Economics
Journal of Inclusion Phenomena and Macrocyclic Chemistry | Year: 2011

Based on our former experience on contaminant solubilisation and mobilisation in the process of soil remediation we used cyclodextrins as additives in environmental bioassays, for improving solubility and bioavailability of the contaminant in soil and as a consequence sensitivity of the bioassay. In this article we introduce the findings on the application of RAMEB (randomly methylated β-cyclodextrin) for testing PCP (pentachlorophenol) in soil, in three bioassays: bacterial luminescence- inhibition test with Vibrio fischeri, protozoon growth inhibition test with Tetrahymena pyriformis, and Ames mutagenicity test. We applied RAMEB which has a high solubilising capacity on many typical soil contaminant and PCP, because contradictory results were published for its toxicity and mutagenicity. The RAMEB-aided Ames test, gave a sudden and expressed increase in the mutagenicity of PCP, however, Ames mutagenicity was negative without cyclodextrin (CD). Based on these results we tried to apply RAMEB for increasing sensitivity of other bioassays, such as acute toxicity tests with different test organisms. According to our results the effect of RAMEB on bioavailability and toxic effect depends not only on the K ow value (octanol-water partition coefficient) of the chemical substances, but also on the test organism, the water-content of the test-matrix and the applied concentration of RAMEB, as well as its ratio to PCP. We collected all the characteristics of the bioassays applied for PCP and some other contaminants and showed the measured effect data in comparison with each other. We found that in the complex system of soil and soil suspension, used in the bioassays, the interactions between soil solid, water and gaseous phases, as well as between the test organism and RAMEB result in K ow dependent partition of the contaminant between solid and water phases of soil, RAMEB, and the test organism. The conclusion is that RAMEB undoubtedly has an influence on the fate and behaviour of the contaminant in soil and soil suspensions, and the direction of the RAMEB-induced changes depends on the effective concentration of the RAMEB in the bioassay, the time of contact, the type of test organism, and the characteristics of the RAMEB-contaminant complex. In those cases, when RAMEB increased the effect of a contaminated environmental sample, this CD-induced increase can be considered as a "realistic worse case" situation, which can be very useful in risk assessment, resulting in a moderate overestimate in the value of environmental risk. © 2010 Springer Science+Business Media B.V.

Fenyvesi E.,Cyclolab Cyclodextrin R and D Laboratory Ltd. | Balogh K.,Cyclolab Cyclodextrin R and D Laboratory Ltd. | Olah E.,Cyclolab Cyclodextrin R and D Laboratory Ltd. | Batai B.,Budapest University of Technology and Economics | And 3 more authors.
Journal of Inclusion Phenomena and Macrocyclic Chemistry | Year: 2011

The effect of random methylated βCD (RAMEB) on the efficiency of various remediation technologies was studied in lab-scale model-experiments applying soil and groundwater originating from a site contaminated with trichloroethylene (TCE). The solubility of TCE was enhanced to tenfold in 10% solution of RAMEB compared to that in water. This solubilizing effect was utilized for remediation of the TCE contaminated soil using enhanced groundwater extraction and in situ TCE oxidation by ISCO (= in situ chemical oxidation). The effect of CD on TCE extraction from soil was studied using two technologies: ground-water extraction followed by air stripping or UV irradiation. The RAMEB-enhanced ISCO was applied directly to the water-saturated soil without water extraction or separation. The efficiency of air stripping of TCE (removal by bubbling air through the contaminated ground-water obtained by extraction) was decreased in the presence of RAMEB due to the volatility decreasing effect of complexation. The efficiency of the entire technology (extraction and air stripping together) was, however, enhanced as three times more TCE was dissolved, and more than twice as much could be removed when 5% RAMEB solution was applied instead of water. Similar results were obtained by UV irradiation. Although the complexation has a protective effect against degradation caused by irradiation, the efficiency of the technology (extraction and subsequent UV irradiation) is enhanced to approximately threefold, because more than 10 times higher TCE concentration was found in the extract using 20% RAMEB concentration. ISCO is based on Fe-catalyzed oxidation using hydrogen peroxide. The catalytic effect of RAMEB was observed only when it was applied together with Fe(II) salts. Without Fe(II) the effect of complex formation dominated. When hydrogen peroxide and FeSO4 were applied with RAMEB, over five times enhancement in TCE removal was obtained compared to the technology based on the addition of hydrogen peroxide and Fe(II) salts without RAMEB. This effect shows that the solubilizing effect on iron catalyst is at least as much or even more important than the solubilizing effect on TCE. The ternary complex formation with ferrous/ferric ion and TCE seems to be responsible for the enhanced efficacy. © 2010 Springer Science+Business Media B.V.

Fekete-Kertesz I.,Budapest University of Technology and Economics | Molnar M.,Budapest University of Technology and Economics | Atkari A.,WEPROT Ltd. | Gruiz K.,Budapest University of Technology and Economics | Fenyvesi E.,Cyclolab Cyclodextrin R and D Laboratory Ltd.
Periodica Polytechnica: Chemical Engineering | Year: 2013

In this paper we present the remediation possibilities of a trichloroethylene contaminated site of a former metalworking plant in Hungary, where high TCE concentration (150 μg/L to 35.000 μg/L) was detected in the groundwater. Lab-scale experiments were performed to compare the potential bioremediation technology-alternatives eg.: enhanced biodegradation; pump & treat by UV irradiation (photodegradation); in situ chemical oxidation (ISCO) applying different oxidants (KMnO4, Na2S2O8and H2O2). The lab-scale experiments showed in all cases reduction of the TCE-concentration of the water. Comparing the removal efficacy and concerning the time requirement ISCO was the most effective in laboratory studies.

Varga G.,ChiroQuest Chiral Technologies Development Ltd. | Fodor G.,University of Szeged | Ilisz I.,University of Szeged | Szeman J.,Cyclolab Cyclodextrin R and D Laboratory Ltd. | And 3 more authors.
Journal of Pharmaceutical and Biomedical Analysis | Year: 2012

Three β-cyclodextrin-based chiral stationary phases were developed applying novel bonding chemistry. The separation performances of β-cyclodextrin, (R,. S)-2-hydroxypropyl-β-cyclodextrin, and permethyl-β-cyclodextrin-based CSPs were compared in the resolution of structurally divergent analytes, such as coumarins, dansyl amino acids, and propionic acid derivatives. Separations were carried out in reversed phase mode applying 0.1% triethylammonium phosphate (pH 3.5)/MeOH mobile phase systems in different compositions. Of the three novel CSPs the permethyl-β-cyclodextrin bonded phase proved to be the most effective one for the enantioseparation of investigated analytes. © 2012 Elsevier B.V.

Fenyvesi F.,Debrecen University | Reti-Nagy K.,Debrecen University | Bacso Z.,Debrecen University | Gutay-Toth Z.,Debrecen University | And 9 more authors.
PLoS ONE | Year: 2014

Cyclodextrins are widely used excipients for increasing the bioavailability of poorly water-soluble drugs. Their effect on drug absorption in the gastrointestinal tract is explained by their solubility- and permeability-enhancement. The aims of this study were to investigate penetration properties of fluorescently labeled randomly methylated-beta-cyclodextrin (FITC-RAMEB) on Caco-2 cell layer and examine the cellular entry of cyclodextrins on intestinal cells. The permeability of FITC-RAMEB through Caco-2 monolayers was very limited. Using this compound in 0.05 mM concentration the permeability coefficient was 3.35±1.29x10-8 cm/s and its permeability did not change in the presence of 5 mM randomly methylated-beta-cyclodextrin. Despite of the low permeability, cellular accumulation of FITC-RAMEB in cytoplasmic vesicles was significant and showed strong time and concentration dependence, similar to the characteristics of the macropinocytosis marker Lucifer Yellow. The internalization process was fully inhibited at 0°C and it was drastically reduced at 37°C applying rottlerin, an inhibitor of macropinocytosis. Notably, FITC-RAMEB colocalized with the early endosome organizer Rab5a. These results have revealed that FITC-RAMEB is able to enter intestinal epithelial cells by fluid-phase endocytosis from the apical side. This mechanism can be an additional process which helps to overcome the intestinal barrier and contributes to the bioavailability enhancement of cyclodextrins. © 2014 Fenyvesi et al.

Kiss T.,Debrecen University | Fenyvesi F.,Debrecen University | Bacskay I.,Debrecen University | Varadi J.,Debrecen University | And 5 more authors.
European Journal of Pharmaceutical Sciences | Year: 2010

Several β-cyclodextrin (β-CD) derivatives have been synthesized recently to improve the physicochemical properties and inclusion capacities of the parent molecule, however, there is limited information available about their cytotoxic effects. In this study we investigated the cytotoxic and hemolytic properties of various β-CDs in correlation with their cholesterol-solubilizing capacities to expose the mechanism of toxicity. MTT cell viability test, performed on Caco-2 cells showed significant differences between the cytotoxicity of β-CD derivatives. Cell toxicity of methylated-β-CDs was the highest, while ionic derivatives proved to be less toxic than methylated ones. Most of the second generation β-CD derivatives, having both ionic and methyl substituents showed less cytotoxicity than the parent compounds both on Caco-2 cells and human erythrocytes. Inclusion of cholesterol into the ring of randomly methylated-β-CD and heptakis(2,6-di-. O-methyl)-β-CD abolished the cell toxicity indicating the role of cholesterol extraction in cytotoxicity. These data demonstrate the correlation between the cytotoxic effect, hemolytic activity and the cholesterol complexation attributes of β-CD derivatives and we propose that cholesterol-solubilizing properties can be a predictive factor for β-CD cell toxicity. © 2010 Elsevier B.V.

Szente L.,CycloLab Cyclodextrin RandD Laboratory Ltd. | Puskas I.,CycloLab Cyclodextrin RandD Laboratory Ltd. | Csabai K.,CycloLab Cyclodextrin RandD Laboratory Ltd. | Fenyvesi E.,CycloLab Cyclodextrin RandD Laboratory Ltd.
Chemistry - An Asian Journal | Year: 2014

Self-assembled, noncovalent polymeric biodegradable materials mimicking proteoglycan aggregates were synthesized from inclusion complexes of cationic surfactants with γ-cyclodextrin and the natural anionic polymer hyaluronan. The amorphous structure of this ternary system was proven by X-ray diffraction and thermal analysis. Light-scattering measurements showed that there was a competition between hyaluronic acid and the surfactant for the cyclodextrin cavity. These self-assembled supramolecular matrices were loaded with both hydrophilic and lipophilic drug substances for dissolution studies. The release of the entrapped drugs was found to be controlled by cations in the surrounding media and by biodegradation. Slow drug release in an ion-free medium became faster in physiological salt solution in which the macroscopic polymer matrix was disassembled. In contrast, the enzymatic degradation of hyaluronan was hindered in the polymeric matrix. The supramolecular systems consisting of γ-cyclodextrin as a macrocyclic host, a cationic surfactant guest, and hyaluronic acid as the anionic polymer electrostatically cross-linked by the inclusion complex of the first two was found to be a novel drug-delivery system for the controlled release of traditional drugs such as curcumin and ketotifen and proteins such as bovine serum albumin. Drug deal: Self-assembled, noncovalent polymeric biodegradable materials mimicking proteoglycan aggregates in their structure are synthesized and loaded with both hydrophilic and lipophilic model drugs as well as with bovine serum albumin. The release of the entrapped drugs from the supramolecular matrices is controlled by electrostatic interactions with the cations in the surrounding media and by biodegradation. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

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