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Zenon Lukaszewski – 1st expert on this subject based on the ideXlab platform
bacterial strains isolated from river water having the ability to split Alcohol Ethoxylates by central fissionEnvironmental Science and Pollution Research, 2016Co-Authors: Irena Budnik, Joanna Zembrzuska, Zenon LukaszewskiAbstract:
Alcohol Ethoxylates (AE) are a major component of the surfactant stream discharged into surface water. The “central fission” of AE with the formation of poly(ethylene glycols) (PEG) is considered to be the dominant biodegradation pathway. However, information as to which bacterial strains are able to perform this reaction is very limited. The aim of this work was to establish whether such an ability is unique or common, and which bacterial strains are able to split AE used as a sole source of organic carbon. Four bacterial strains were isolated from river water and were identified on the basis of phylogenetic trees as Enterobacter strain Z2, Enterobacter strain Z3, Citrobacter freundii strain Z4, and Stenotrophomonas strain Z5. Sterilized river water and “artificial sewage” were used for augmentation of the isolated bacteria. The test was performed in bottles filled with a mineral salt medium spiked with surfactant C12E10 (10 mg L−1) and an inoculating suspension of the investigated bacterial strain. Sequential extraction of the tested samples by ethyl acetate and chloroform was used for separation of PEG from the water matrix. LC–MS was used for PEG determination on the basis of single-ion chromatograms. All four selected and investigated bacterial strains exhibit the ability to split fatty Alcohol Ethoxylates with the production of PEG, which is evidence that this property is a common one rather than specific to certain bacterial strains. However, this ability increases in the sequence: Stenotrophomonas strain Z5 < Enterobacter strain Z2 < Enterobacter strain Z3 = Citrobacter freundii strain Z4.
separation and determination of homogenous fatty Alcohol Ethoxylates by liquid chromatography with mulitstage mass spectrometryJournal of Separation Science, 2014Co-Authors: Joanna Zembrzuska, Irena Budnik, Zenon LukaszewskiAbstract:
Alcohol Ethoxylates (AEs) are a significant component of a stream of surfactants directed to the aquatic environment. The aim of this work was the investigation of the dependence of the analytical signals of homogeneous AE homologues on liquid chromatography with tandem mass spectrometry conditions, as well as the separation of AEs from the water matrix and, on this basis, the development of an analytical procedure suitable for the determination of AEs in environmental samples. Homogeneous homologues containing dodecyl moiety and 2–9 oxyethylene subunits were investigated. The analytical signals of the investigated homologues were optimized in terms of concentration of ammonium acetate in the mobile phase (optimum 5 mM) and a column temperature (optimum 35°C) of the liquid chromatography with tandem mass spectrometry system. A separation of AEs from the water matrix by liquid–liquid extraction (ethyl acetate, chloroform) or solid-phase extraction (C18, styrene divinylbenzene, H-RX) was investigated. In a model investigation, the best recoveries (>90%) were obtained with a styrene divinylbenzene cartridge eluted with a 1:1 mixture of chloroform and methanol. However, much worse recoveries were obtained from the river water sample. Better results were obtained for liquid–liquid extraction with ethyl acetate. Recoveries of 62–80% were obtained for homologues having 4–9 oxyethylene subunits, at the lowest spike.
biodegradation of oxo Alcohol Ethoxylates in the continuous flow activated sludge simulation testWater Research, 2002Co-Authors: Andrzej Szymanski, Bogdan Wyrwas, Ewa Bubien, Tatiana Kurosz, Wieslaw Hreczuch, Wlodzimierz Zembrzuski, Zenon LukaszewskiAbstract:
Abstract Biodegradation of two α -methyl branched oxo-Alcohol Ethoxylates (OAE) of different polydispersity: LIAL 125/14 BRD (LIALB) (broad M.W. distribution) and LIAL 125/14 NRD (LIALN) (narrow M.W. distribution), both having an average of 14 oxyethylene subunits (EO) and a C 12–15 alkyl moiety were tested under the continuous flow activated sludge conditions of the classical Husmann plant. Primary biodegradation and concentration of metabolites: free oxo-Alcohol fraction (FOA) and poly(ethylene glycols) (PEG), were measured. PEG were divided into two fractions: short-chained PEG (PEGshch) (1–4 EO) and long-chained PEG (PEGlch)(>4 EO). The indirect tensammetric technique combined with an adequate separation was used for analysis. Central fission was found to be a highly dominating pathway, as is the case with fatty Alcohol Ethoxylates. OAE are highly primarily biodegraded (above 95%). High concentrations of FOA and PEG are formed. Once formed the PEGlch are further fragmented into the PEGshch. Free Alcohol fraction compounds are biodegraded sooner when alkyl moiety is shorter. OAE polydispersity has an influence on the kinetics of biodegradation; PEG formed from LIALN are biodegraded slower and to a lower degree than those from LIALB.
Harald Pasch – 2nd expert on this subject based on the ideXlab platform
analysis of fatty Alcohol Ethoxylates regarding chain length and endgroups by maldi tof ms using collision induced dissociationMacromolecular Chemistry and Physics, 2012Co-Authors: Valentina Mass, K Rode, Frank Rittig, Thomas Ostrowski, Harald PaschAbstract:
MALDI-TOF MS is used to analyze the chain lengths and endgroups of fatty Alcohol Ethoxylates based on the fragmentation behavior in collision-induced dissociation. MALDI-CID-TOF2 of the Ethoxylates results in complex fragmentation patterns that mirror the fragmentation of the ethylene oxide oligomer chain and the fatty alocohol endgroups. Characteristic fragment patterns are obtained that facilitate the interpretation of the fragmentation behavior of the fatty Alcohol Ethoxylates. Linear and branched endgroups can be differentiated and specific fragments are identified that are characteristic for the cleavage between the polymer chain and the endgroup. These “marker” fragments are used to determine the oligomer chain length and the number of carbons per endgroup.
two dimensional chromatography of complex polymers 8 separation of fatty Alcohol Ethoxylates simultaneously by end group and chain lengthJournal of Separation Science, 2010Co-Authors: Jacquesantoine Raust, Wolf Hiller, Adele Bruell, Pritish Sinha, Harald PaschAbstract:
A comprehensive two-dimensional liquid chromatography system was developed to precisely describe the molecular heterogeneity of fatty Alcohol Ethoxylates. The end-group functionality was analyzed by gradient HPLC while ethylene oxide oligomer distributions were characterized by liquid adsorption chromatography. A baseline separation of all functionality fractions irrespective of the ethylene oxide oligomer chain length was achieved on nonpolar X-Terra® C18 with a methanol–water gradient, whereas an isocratic flow of isopropanol–water on a polar Chromolith® Si column gave a separation according to the oligomer chain length without interference of the end-group distribution. The combination of these two methods to conduct online two-dimensional liquid chromatography experiments resulted in a comprehensive two-dimensional picture on the molecular heterogeneity of the sample.
hplc nmr of fatty Alcohol EthoxylatesMagnetic Resonance in Chemistry, 2005Co-Authors: Wolf Hiller, Adele Brull, Dimitris S Argyropoulos, Eberhard Hoffmann, Harald PaschAbstract:
The application of HPLC–NMR for the analysis of a mixture of fatty Alcohol Ethoxylates (FAEs) is described. The use of the new generation, cryogenically cooled probes is investigated in respect of the sensitivity advantage that they provide. The FAE mixture is separated using liquid chromatography at the critical point of adsorption. The ability of the method to differentiate between the different end groups and the degree of polymerization of the mixture constituents is investigated. Both on-flow and stop-flow HPLC–NMR techniques were used together with two-dimensional NMR spectroscopy. The results are compared with those obtained by using an evaporative light scattering detector for the HPLC. Copyright © 2005 John Wiley & Sons, Ltd.
Bernd Trathnigg – 3rd expert on this subject based on the ideXlab platform
liquid exclusion adsorption chromatography a new technique for isocratic separation of nonionic surfactants iv two dimensional separation of fatty Alcohol Ethoxylates with focusing of fractionsJournal of Chromatography A, 2002Co-Authors: Bernd Trathnigg, Christina RappelAbstract:
Abstract Fatty Alcohol Ethoxylates can be analyzed using a combination of liquid chromatography under critical conditions as the first dimension and liquid exclusion–adsorption chromatography as the second dimension. Transfer of fractions from the first to the second dimension is achieved using the full adsorption–desorption (FAD) technique. The peaks of interest in the first dimension are trapped on a short precolumn before injecting them into the second dimension. Full adsorption is achieved by increasing the water content in the mobile phase before the FAD column. When the fractions are desorbed by switching to the mobile phase of the second dimension, they are focused and reconcentrated. In this way, a full resolution of oligomers is achieved. As both dimensions are run in isocratic mode, density and refractive index detection can be applied, which allows an accurate quantitation.
liquid exclusion adsorption chromatography a new technique for isocratic separation of nonionic surfactants iii two dimensional separation of fatty Alcohol EthoxylatesJournal of Chromatography A, 2001Co-Authors: Bernd Trathnigg, Manfred Kollroser, Christina RappelAbstract:
Abstract A quantitatively accurate mapping of lower fatty Alcohol Ethoxylates can be achieved using a combination of liquid chromatography under critical conditions as the first dimension and liquid exclusion–adsorption chromatography as the second dimension. With coupled density and refractive index detection in both dimensions, the contribution of preferential solvation can also be estimated. In most cases, however, the use of refractive index detection alone also yields satisfactory results.
liquid exclusion adsorption chromatography a new technique for isocratic separation of nonionic surfactants ii quantitation in the analysis of fatty Alcohol EthoxylatesJournal of Chromatography A, 2001Co-Authors: Bernd TrathniggAbstract:
Abstract A new technique of liquid chromatography, which allows baseline separation of fatty Alcohol Ethoxylates with up to 15–20 ethylene oxide units under isocratic conditions allows an accurate quantitative analysis of single hydrophobic chain surfactants. Using density and refractive index detection, the accurate weight fractions of the individual oligomers are obtained. Moreover, the contribution of preferential solvation can be determined. With refractive index detection alone, good accuracy can also be achieved.