Jose Carvalho

Printed version Agribusiness Global Jan/Feb 2019 edition, page 11. Overview of the new "fertilisers" regulation ahead of its approval by the European Union in Summer 2019.

China Ministry of Agriculture (MoA) has been implementing considerable changes regarding the use of agriculture pesticides, particularly in the field of environmental safety and defining the protection goals for risk assessment of pesticides.
The new Chinese regulations on the Management of Pesticides (State Council Decree No.677) entered into force on June 1st, 2017 with a main supporting guidance document released soon after, on August 1st, the Pesticide Registration Management Measures… Mehr anzeigen

China Ministry of Agriculture (MoA) has been implementing considerable changes regarding the use of agriculture pesticides, particularly in the field of environmental safety and defining the protection goals for risk assessment of pesticides.
The new Chinese regulations on the Management of Pesticides (State Council Decree No.677) entered into force on June 1st, 2017 with a main supporting guidance document released soon after, on August 1st, the Pesticide Registration Management Measures (MOA Order [2017] No.3). This guidance document brings about major changes for registrants: a) by introducing risk assessment approaches to assess the environmental safety of pesticides ahead of approval decisions; 2) encouraging companies to bring to the Chinese market more innovative and environmental-friendly products. Weniger anzeigen

Bile acids are relevant markers for clinical research. This study reports the production of antibodies for isolithocholic acid, the isomer of the extensively studied lithocholic acid. The IgG titer and affinity maturation were monitored during the immunizations of three mice and two rabbits. In both animal models, polyclonal antibodies with a high selectivity and affinity were produced. The development of a direct competitive ELISA with a test midpoint of 0.69 ± 0.05 µg/L and a measurement… Mehr anzeigen

Bile acids are relevant markers for clinical research. This study reports the production of antibodies for isolithocholic acid, the isomer of the extensively studied lithocholic acid. The IgG titer and affinity maturation were monitored during the immunizations of three mice and two rabbits. In both animal models, polyclonal antibodies with a high selectivity and affinity were produced. The development of a direct competitive ELISA with a test midpoint of 0.69 ± 0.05 µg/L and a measurement range from 0.09 to 15 µg/L is reported. Additionally, the crystal structure of isolithocholic acid is described for the first tim. Weniger anzeigen

Bile acids are relevant markers for clinical research. This study reports the production of antibodies for isolithocholic acid, the isomer of the extensively studied lithocholic acid. The IgG titer and affinity maturation were monitored during the immunizations of three mice and two rabbits. In both animal models, polyclonal antibodies with a high selectivity and affinity were produced. The development of a direct competitive ELISA with a test midpoint of 0.69 ± 0.05 µg/L and a measurement… Mehr anzeigen

Bile acids are relevant markers for clinical research. This study reports the production of antibodies for isolithocholic acid, the isomer of the extensively studied lithocholic acid. The IgG titer and affinity maturation were monitored during the immunizations of three mice and two rabbits. In both animal models, polyclonal antibodies with a high selectivity and affinity were produced. The development of a direct competitive ELISA with a test midpoint of 0.69 ± 0.05 µg/L and a measurement range from 0.09 to 15 µg/L is reported. Additionally, the crystal structure of isolithocholic acid is described for the first time. Weniger anzeigen

The synthesis of a novel PS conjugated with bovine and human serum albumin (BSA and HSA) and a monoclonal antibody anti-CD104 is reported, as well as their biological potential against the human bladder cancer cell line UM-UC-3. No photodynamic effect was detected when the non-conjugated porphyrin was used. Yet, when it was coupled covalently with the mAb anti-CD104, BSA and HSA, the resulting photosensitizer conjugates demonstrated high efficacy in destroying the cancer cells, the mAb… Mehr anzeigen

The synthesis of a novel PS conjugated with bovine and human serum albumin (BSA and HSA) and a monoclonal antibody anti-CD104 is reported, as well as their biological potential against the human bladder cancer cell line UM-UC-3. No photodynamic effect was detected when the non-conjugated porphyrin was used. Yet, when it was coupled covalently with the mAb anti-CD104, BSA and HSA, the resulting photosensitizer conjugates demonstrated high efficacy in destroying the cancer cells, the mAb anti-CD104 efficacy overruling the albumins. Weniger anzeigen

Sensitive und selektive Immunoassays unterstützen Untersuchungen im Vollzug der EU Wasserrahmenrichtlinie. Sie erlauben, eine hohe Anzahl von Proben ohne Anreicherungsschritte zu untersuchen und ermöglichen daher den Aufbau eines zeitlich und räumlich engmaschigen Messnetzes. Mit Hilfe von ELISA (enzymelinked immunosorbent assay) wurde ein Gewässerscreening in Berlin durchgeführt. Rudolf Schneider

Carbamazepine (CBZ), caffeine and cetirizine were monitored by enzyme-linked immunosorbent assays (ELISAs) in surface and wastewaters from Berlin, Germany. This fast and cost-efficient method enabled to assess the spatial and temporal variation of these anthropogenic markers in a high-throughput screening. CBZ and cetirizine were detected by the same antibody, which selectively discriminates between both compounds depending on the pH value used in the incubation step. To our best knowledge… Mehr anzeigen

Carbamazepine (CBZ), caffeine and cetirizine were monitored by enzyme-linked immunosorbent assays (ELISAs) in surface and wastewaters from Berlin, Germany. This fast and cost-efficient method enabled to assess the spatial and temporal variation of these anthropogenic markers in a high-throughput screening. CBZ and cetirizine were detected by the same antibody, which selectively discriminates between both compounds depending on the pH value used in the incubation step. To our best knowledge, this is the first dual-analyte immunoassay working with a single antibody. The frequent sampling with 487 samples being processed allowed for the repeated detection of unusually high concentrations of CBZ and caffeine. ELISA results correlate well with the ones obtained by liquid chromatography tandem mass spectrometry (LC-MS/MS). Caffeine concentrations found in surface waters were elevated by combined sewer overflows after stormwater events. During the hay fever season, the concentrations of the antihistamine drug cetirizine increased in both surface and wastewaters. Caffeine was almost completely removed during wastewater treatment, while CBZ and cetirizine were found to be more persistent. The maximum concentrations of caffeine, CBZ and cetirizine found in influent wastewater by LC-MS/MS were 470, 5.0 and 0.49 μg L(-1), while in effluent wastewater the concentrations were 0.22, 4.5 and 0.51 μg L(-1), respectively. For surface waters, concentrations up to 3.3, 4.5 and 0.72 μg L(-1) were found, respectively. Weniger anzeigen

Caffeine is a useful indicator to quickly assess liver function. High-throughput tests are needed for single-point caffeine measurements, with low cross-reactivity toward its major metabolite, paraxanthine. A newly developed ELISA was compared with an LC-MS/MS reference method, using 60 saliva samples from 10 individuals, before and after caffeine intake. Bland-Altman plot, Student t-test and F-test were used to compare the two methods. Proteins were precipitated using organic solvent and the… Mehr anzeigen

Caffeine is a useful indicator to quickly assess liver function. High-throughput tests are needed for single-point caffeine measurements, with low cross-reactivity toward its major metabolite, paraxanthine. A newly developed ELISA was compared with an LC-MS/MS reference method, using 60 saliva samples from 10 individuals, before and after caffeine intake. Bland-Altman plot, Student t-test and F-test were used to compare the two methods. Proteins were precipitated using organic solvent and the caffeine recoveries compared with those obtained using sample microfiltration. The antibody, with a low cross-reactivity toward paraxanthine (0.08%), allows quantification of caffeine in saliva samples from 2.5 µg/L to 125 µg/L with high precision and the ELISA shows comparable results to those obtained by LC-MS/MS. A one-step protein precipitation using an organic solvent provides comparable results to a more costly and time-consuming microfiltration pre-treatment of samples. The new ELISA is a fit-for-purpose method to accurately and precisely determine caffeine in saliva samples. Weniger anzeigen

Book chapter on food chemistry: Caffeine covers the latest knowledge in a uniquely structured format and is specifically designed to link chemistry with health and nutrition to provide a broad, appealing book. Coverage begins with caffeine in relation to nutrition focussing on beverages, then concentrates on chemistry, crystal structures of complexes in caffeine and biochemistry. In the analysis chapters, assays are conducted by LC-MS, capillary electrophoresis, automated flow methods and… Mehr anzeigen

Book chapter on food chemistry: Caffeine covers the latest knowledge in a uniquely structured format and is specifically designed to link chemistry with health and nutrition to provide a broad, appealing book. Coverage begins with caffeine in relation to nutrition focussing on beverages, then concentrates on chemistry, crystal structures of complexes in caffeine and biochemistry. In the analysis chapters, assays are conducted by LC-MS, capillary electrophoresis, automated flow methods and immunoassay methods. The effects of caffeine on the brain, cognitive performance, sleep, oxidative damage, exercise and pulmonary function are all considered in the closing section of the book. Weniger anzeigen

A non-invasive method to monitor the humoral immune response in mice after immunization is described. From fecal pellets of an individual mouse, a sufficient amount of active immunoglobulins or their fragments can be extracted to perform a regular examination of the status of the immune response by immunoassay. Hapten-specific antibodies from the feces of mice from three immunization trials showed very similar characteristics to those obtained from serum at a given date. Therefore, it can be… Mehr anzeigen

A non-invasive method to monitor the humoral immune response in mice after immunization is described. From fecal pellets of an individual mouse, a sufficient amount of active immunoglobulins or their fragments can be extracted to perform a regular examination of the status of the immune response by immunoassay. Hapten-specific antibodies from the feces of mice from three immunization trials showed very similar characteristics to those obtained from serum at a given date. Therefore, it can be suspected that some serum IgG enters the intestinal lumen and ends up in the feces, where they appear to be considerably stable. Hapten-specific IgAs were not found in the feces. Being able to analyze antibody titers in feces could be an interesting animal welfare refinement to standard practice that does not entail repeated blood sampling.
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Book chapter on caffeine chemistry.

HPLC, ELISA, antibodies, monoclonal antibody, LC-MS/MS, water, Caffeine, coprostanol, surface water, markers of human contamination, Immunoassay, dispersive liquid-liquid microextraction (DLLME), liquid chromatography tandem mass spectrometry, saliva, isolithocholic acid, ILA, bile acids, polyclonal antibodies, environmental chemistry, pollution, immunoglobulin G, hybridoma, Cholesterol, Cholestanol, Cholestanone, Ergosterol, Stigmasterol

A new immunoassay has been developed based on a commercially available anti-caffeine monoclonal antibody and a de novo synthesized tracer, using horseradish peroxidase and UV-visible detection. Caffeine, which is frequently found in surface waters, can be quantified with a relative error lower than 20% for concentrations above 0.025 microg L(-1) (limit of quantitation, direct analysis). The limit of detection is 0.001 microg L(-1) and can be reduced by solid-phase extraction (SPE). Moreover… Mehr anzeigen

A new immunoassay has been developed based on a commercially available anti-caffeine monoclonal antibody and a de novo synthesized tracer, using horseradish peroxidase and UV-visible detection. Caffeine, which is frequently found in surface waters, can be quantified with a relative error lower than 20% for concentrations above 0.025 microg L(-1) (limit of quantitation, direct analysis). The limit of detection is 0.001 microg L(-1) and can be reduced by solid-phase extraction (SPE). Moreover, with minor adaptations, the assay can be used to quantify caffeine in several beverages, shampoo, and caffeine tablets. The results obtained by ELISA correlate well with those from liquid chromatography-tandem mass spectrometry (LC-MS-MS) for the tested matrices. Several surface waters from Berlin were analysed and all tested positive for caffeine, with concentrations higher than 0.030 microg L(-1). In one run 66 samples can be analysed within 2 h. Weniger anzeigen

European Council Directive 98/83/EC on the quality of water intended for human consumption brought a new challenge for water-quality control routine laboratories, mainly on pesticides analysis. Under the guidelines of ISO/IEC 17025:2005, a multiresidue method was developed, validated, implemented in routine, and studied with real samples during a one-year period. The proposed method enables routine laboratories to handle a large number of samples, since 28 pesticides of 14 different chemical… Mehr anzeigen

European Council Directive 98/83/EC on the quality of water intended for human consumption brought a new challenge for water-quality control routine laboratories, mainly on pesticides analysis. Under the guidelines of ISO/IEC 17025:2005, a multiresidue method was developed, validated, implemented in routine, and studied with real samples during a one-year period. The proposed method enables routine laboratories to handle a large number of samples, since 28 pesticides of 14 different chemical groups can be quantitated in a single procedure. The method comprises a solid-phase extraction step and subsequent analysis by liquid chromatography-mass spectrometry (LC-MS-MS). The accuracy was established on the basis of participation in interlaboratory proficiency tests, with encouraging results (majority |z-score| <2), and the precision was consistently analysed over one year. The limits of quantitation (below 0.050 μg L−1) are in agreement with the enforced threshold value for pesticides of 0.10 μg L−1. Overall method performance is suitable for routine use according to accreditation rules, taking into account the data collected over one year. Weniger anzeigen

Water contamination with volatile organic compounds (VOCs) are traceable to leaking underground fuel reservoirs, solvent storage vessels, agricultural practices, industrial residues, and deficient wastewater treatment and disposal. In order to perform effective monitoring of such organic micropollutants in a straightforward manner, a multiresidue method for the determination of 23 VOCs (trihalomethanes (THMs), BTEX and chlorinated solvents) in water has been developed using solid-phase… Mehr anzeigen

Water contamination with volatile organic compounds (VOCs) are traceable to leaking underground fuel reservoirs, solvent storage vessels, agricultural practices, industrial residues, and deficient wastewater treatment and disposal. In order to perform effective monitoring of such organic micropollutants in a straightforward manner, a multiresidue method for the determination of 23 VOCs (trihalomethanes (THMs), BTEX and chlorinated solvents) in water has been developed using solid-phase microextraction (SPME) and capillary gas chromatography–mass spectrometry (GC–MS). This group includes also methyl-tert-butyl ether, epichlorhydrine, and vinyl chloride which present additional analytical difficulties. Three different fibres were assayed: 7-µm polydimethylsiloxane (PDMS), 100-µm PDMS, and 75-µm Carboxen-PDMS, and the extraction conditions were optimized. The best results for the majority of the analytes and mainly for those with the lowest signals were obtained using the Carboxen-PDMS fibre after 15 min of extraction in the headspace mode at a room temperature of 20 ± 2°C. The analytical sensitivity, linearity, precision, accuracy, and uncertainties have been studied for method validation in agreement with the international standard ISO/IEC 17025:2005. The limits of detection achieved with the proposed method (0.06–0.17 µg L−1) are adequate to determine the VOCs at the restrictive levels established by the European legislation. This was a decisive achievement to enable the analysis of all VOCs listed under the drinking-water directive in a single assay. The method exhibits performance capabilities suitable for routine analysis of VOCs in drinking-water by quality-control laboratories as enforced by EU Directives. The method is currently being used for this purpose, and participation in proficiency tests was assessed, with encouraging results. Weniger anzeigen

An environmentally friendly methodology is proposed for the analysis of pesticides in soil samples based on supercritical fluid extraction (SFE) and analysis at high selectivity and sensitivity, by gas chromatography–tandem mass spectrometry (GC–MS–MS). The pesticides investigated are among the most commonly used in intensive horticulture activities comprising organochlorine and organophosphorous insecticides, triazine and acetanilide herbicides, amongst others. An experimental design approach… Mehr anzeigen

An environmentally friendly methodology is proposed for the analysis of pesticides in soil samples based on supercritical fluid extraction (SFE) and analysis at high selectivity and sensitivity, by gas chromatography–tandem mass spectrometry (GC–MS–MS). The pesticides investigated are among the most commonly used in intensive horticulture activities comprising organochlorine and organophosphorous insecticides, triazine and acetanilide herbicides, amongst others. An experimental design approach was used for modelling SFE and optimised extraction conditions were derived for the total pesticides extraction or for specific sub-groups of interest. Pesticide residues could be detected in soils in the sub-ppb range (0.1–3.7 μg kg−1), with quite good precision (4.2–15.7%) and extraction efficiency (80.4–106.5%). The analysis of soil samples from an intensive horticulture area in Póvoa de Varzim, north of Portugal, revealed the presence of persistent pesticides, parent compounds and degradation products among the following: endosulfan, endosulfan sulfate, dieldrin, 4,4′-DDE, 4,4′-DDD, atrazine, alachlor, metolachlor, chlorpyrifos, pendimethalin and lindane. The important features to point out are the easy interpretation of chromatograms and straightforward confirmation of analytes that greatly facilitates the analyst judgement on the contamination of the sample. Weniger anzeigen

The title compound [systematic name: 6-(1,3-dimethyl-2,6-dioxo-2,3,6,7-tetrahydro-1H-purin-7-yl)hexanoic acid monohydrate, CAS 61444-23-3], C13H18N4O4·H2O, was synthesized and crystallized from ethyl acetate. Hydrogen bonds between xanthine and water molecules contribute to the formation of layers parallel to (10~2).