TY - JOUR A1 - Lima, D.L.D. A1 - Schneider, Rudolf A1 - Scherer, H.W. A1 - Duarte, A.C. A1 - Santos, E.B.H. A1 - Esteves, V.I. T1 - Sorption-desorption behavior of atrazine on soils subjected to different organic long-term amendments JF - Journal of agricultural and food chemistry N2 - Sorption of atrazine on soils subjected to three different organic amendments was measured using a batch equilibrium technique. A higher KF value (2.20 kg-1(mg L-1)-N) was obtained for soil fertilized with compost, which had a higher organic matter (OM) content. A correlation between the KFOC values and the percentage of aromatic carbon in OM was observed. The highest KFOC value was obtained for the soil with the highest aromatic content. Higher aromatic content results in higher hydrophobicity of OM, and hydrophobic interactions play a key role in binding of atrazine. On the other hand, the soil amended with farmyard manure had a higher content of carboxylic units, which could be responsible for hydrogen bonding between atrazine and OM. Dominance of hydrogen bonds compared to hydrophobic interactions can be responsible for the lower desorption capacity observed with the farmyard manure soil. The stronger hydrogen bonding can reduce the leaching of atrazine into drinking water resources and runoff to rivers and other surface waters. KW - Capillary electrophoresis KW - Atrazine KW - Sorption KW - Soil KW - Compost KW - Sewage sludge KW - Farmyard manure PY - 2010 DO - https://doi.org/10.1021/jf903937d SN - 0021-8561 SN - 1520-5118 VL - 58 IS - 5 SP - 3101 EP - 3106 PB - American Chemical Society CY - Columbus, Ohio AN - OPUS4-21108 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lima, D.L.D. A1 - Schneider, Rudolf A1 - Esteves, V.I. T1 - Sorption behavior of EE2 on soils subjected to different long-term organic amendments JF - The science of the total environment N2 - The transport and fate of hydrophobic organic contaminants in the environment involve complex phenomena that are influenced by many processes that include sorption by soil components. Sorption behavior of EE2 molecules onto different soil samples was studied and results correlated with the content and type of organic matter present. The highest Κ value, among all soils presented in this study, was obtained for soil fertilized with compost (1.22) which presented the highest organic carbon content. Also the sorption behavior depends greatly on the soil specific organic matter characteristics. A strong positive correlation was observed between aromatic and carboxylic units and ΚOC values. The results also suggested an association of the EE2 aromatic nuclei face to face with the surface and/or another EE2 molecule and also sorbent–sorbate interactions due to hydrogen or covalent bonding, likely to occur due to the presence of phenolic function at C-3 and hydroxyl function at C-17 of the EE2 molecules that can react with carboxylic functional groups of soil organic matter. The stronger EE2 sorbs to soil organic matter lower is the leaching into drinking water resources and runoff to rivers and surface water, minimizing its residual toxicity. KW - EE2 KW - Sorption KW - Soil KW - Deconvolution KW - Fluorescence PY - 2012 DO - https://doi.org/10.1016/j.scitotenv.2012.02.014 SN - 0048-9697 VL - 423 SP - 120 EP - 124 PB - Elsevier CY - Amsterdam AN - OPUS4-25739 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Silva, C.P. A1 - Lima, D.L.D. A1 - Schneider, Rudolf A1 - Otero, M. A1 - Esteves, V.I. T1 - Evaluation of the anthropogenic input of caffeine in surface waters of the north and center of Portugal by ELISA JF - The science of the total environment N2 - This study comprises the development of an enzyme-linked immunosorbent assay (ELISA) for the quantification of caffeine in complex aqueous matrices without any sample clean-up procedure. Salinity and dissolved organic matter were selected as potential interfering agents. The addition of a sample buffer containing bovine serum albumin (BSA) prior to the sample was found to decrease the influence of those interfering agents. The working range of the developed method was 0.1–100 µg L- 1. Quantification of caffeine was possible in 43 out of 51 real aqueous samples, at values between < LOD and 15 µg L- 1. Results correlate well with those obtained by LC–MS/MS. To the best of our knowledge this is the first study dealing with the quantification of caffeine in Portugal's surface waters. KW - Caffeine KW - Surface water KW - ELISA KW - Anthropogenic markers KW - Koffein KW - Eintrag KW - Oberflächenwasser KW - Gewässer KW - Abwasser KW - Antikörper KW - Immunoassay PY - 2014 DO - https://doi.org/10.1016/j.scitotenv.2014.01.120 SN - 0048-9697 VL - 479-480 SP - 227 EP - 232 PB - Elsevier CY - Amsterdam AN - OPUS4-30450 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Silva, C.P. A1 - Lima, D.L.D. A1 - Schneider, Rudolf A1 - Otero, M. A1 - Esteves, V.I. T1 - Development of ELISA methodologies for the direct determination of 17beta-estradiol and 17alpha-ethinylestraydiol in complex aqueous matrices JF - Journal of environmental management N2 - This study comprises the development of enzyme-linked immunosorbent assays (ELISAs) for the quantification of 17β-estradiol (E2) and 17α-ethinylestradiol (EE2) in complex aqueous matrices without any sample clean-up procedures. Salinity and dissolved organic matter were selected as potential interfering agents in the analysis of E2 and EE2. The optimization was performed in order to (i) overcome matrix effects, and to (ii) increase sensitivity. The addition of a sample buffer containing bovine serum albumin (BSA) prior to the sample was found to decrease the influence of matrix effects. Moreover, adjustments of this buffer's pH together with the optimization of tracer (T) dilution and incubation time were undertaken in order to lower the quantification range. The optimized methods allowed the quantification of E2 and EE2 in the ranges 0.03–200 µg L-1 and 0.02–10 µg L-1, respectively. The assays were applied to real aqueous samples. It was possible to do a first approach to the levels of E2 in Portuguese surface and waste waters; however, it was not feasible to detect EE2 in the samples tested. KW - Enzyme-linked immunosorbent assay KW - Endocrine disrupting compounds KW - 17beta-Estradiol KW - 17alpha-Ethinylestradiol KW - Surface water KW - Wastewater PY - 2013 DO - https://doi.org/10.1016/j.jenvman.2013.03.041 SN - 0301-4797 SN - 1095-8630 VL - 124 SP - 121 EP - 127 PB - Elsevier Ltd. CY - Amsterdam AN - OPUS4-28516 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lima, D.L.D. A1 - Schneider, Rudolf A1 - Esteves, V.I. T1 - Development of an enzyme-linked immunosorbent assay for atrazine monitoring in water samples JF - Environmental science and pollution research international N2 - The implementation of the Water Framework Directive (2000/60/EC) requires the establishment of monitoring programs. However, conventional procedures for sample preparation prior to chromatographic analysis are rather expensive and time consuming, being the development of cost-effective and easy tool a necessity. The aim of this work was to develop an enzyme-linked immunosorbent assay (ELISA) able to determine atrazine in water samples. Matrix effects evaluation showed that the increase of humic acid (HA) concentration leads to flattened calibration curves and to the loss of the sigmoidal shape. However, such interference was overcome, by the presence of an environmental sample buffer, incubated together with the samples. Recoveries from 88.5 to 119.2 % were obtained in the presence of HA concentrations up to 20 mg-1. An analytical range from 0.003 to 1 µgL-1 was obtained, and atrazine was detected in a sewage treatment plant with concentrations ranging from 14 to 52 ngL-1. KW - Immunoassay KW - Atrazine KW - Surface waters KW - Wastewater treatment plants KW - Matrix effects PY - 2013 DO - https://doi.org/10.1007/s11356-012-1227-z SN - 0944-1344 SN - 1614-7499 VL - 20 IS - 5 SP - 3157 EP - 3164 PB - Ecomed Publ. CY - Landsberg AN - OPUS4-28299 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lima, D.L.D. A1 - Silva, C.P. A1 - Schneider, Rudolf A1 - Esteves, V.I. T1 - Development of an ELISA procedure to study sorption of atrazine onto a sewage sludge-amended luvisol soil JF - Talanta N2 - Pesticides may contaminate ground and surface waters and one of the major factors governing this property is soil sorption. Sorption can be assessed by batch equilibrium technique which produces lots of extracts with high dissolved organic carbon concentration in which the pesticide concentration has to be determined. We developed an ELISA procedure to analyse atrazine based on polyclonal antibodies (C193) for which tracer structure and dilutions of immunochemical reagents were adapted to fit the purpose. After a 1000-fold dilution (or after an SPE clean-up procedure) extracts of a sewage-sludge amended luvisol (used as an example application of the methodology developed) could be reliably analysed. The Freundlich model is able to describe adsorption for this system (r² = 0.977) delivering a distribution coefficient KF of 1.6 ± 0.2 (mg kg-1) (mg L-1)-N and an isotherm nonlinearity factor N of 0.70 ± 0.09. KW - ELISA KW - Atrazine KW - Sorption PY - 2011 DO - https://doi.org/10.1016/j.talanta.2011.06.024 SN - 0039-9140 VL - 85 IS - 3 SP - 1494 EP - 1499 PB - Elsevier B.V. CY - Amsterdam AN - OPUS4-24305 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Lima, D.L.D. A1 - Silva, C.P. A1 - Schneider, Rudolf A1 - Otero, M. A1 - Esteves, V.I. T1 - Application of dispersive liquid-liquid microextraction for estrogens' quantification by enzyme-linked immunosorbent assay JF - Talanta N2 - Estrogens, such as 17β-estradiol (E2) and 17α-ethinylestradiol (EE2), are the major responsible for endocrine-disrupting effects observed in aquatic environments due to their high estrogenic potency, even at concentrations ranging from pg L-1 to ng L-1. Thus, it is essential to develop analytical methodologies suitable for monitoring their presence in water samples. Dispersive liquid–liquid microextraction (DLLME) was used as a pre-concentration step prior to the quantification of E2 and EE2 by enzyme-linked immunosorbent assay (ELISA). First, an evaluation of the effect of DDLME on the E2 and EE2 ELISA calibration curves was performed. Since the extraction procedure itself had an influence on the ELISA optical density (OD), it became necessary to subject, not only the samples, but also all the standards to the DLLME process. Working ranges were determined, being between 1.2 and 8000 ng L-1, for E2, and between 0.22 and 1500 ng L-1, for EE2. The influence of organic matter, both in the extraction and quantification, was evaluated and it was observed that its presence in the solution did not affect considerably the calibration curve. Recovery rates were also determined, ranging from 77% to 106% for ultrapure water and from 104% to 115% for waste water samples, the most complex ones in what concerns matrix effects. Results obtained when applying the proposed method to real water samples can be considered quite satisfying. Moreover, the obtained working ranges encompass values generally reported in literature, confirming the practical use of the method for environmental samples. KW - DLLME KW - ELISA KW - Water samples KW - Environment KW - 17beta-estradiol KW - 17alpha-ethinylestradiol PY - 2014 DO - https://doi.org/10.1016/j.talanta.2014.02.069 SN - 0039-9140 VL - 125 SP - 102 EP - 106 PB - Elsevier CY - Amsterdam AN - OPUS4-30614 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -