Immunoanalytical approaches for the control of xenobiotics and biotoxins in foodstuffs

 Effective control of food quality and safety requires analytical methods that guarantee the reliable determination of any substance potentially harmful to the consumer that may be present in the food prior to its distribution and marketing. One of the analytical approaches that contributes to guarantee this objective encompasses a series of techniques that have in common the use of antibodies as essential elements for the detection of the target analyte, and which together are called immunochemical methods. This article aims to provide a basic overview of the biochemical principles underlying these technologies and their advantages and limitations in the determination of chemical contaminants, residues and additives in food matrices. The last part discusses some of our initiatives in this field that have resulted in commercially available rapid kits after transferring the corresponding technology to the industrial sector

Haptenos, conjugados y anticuerpos para el fungicida ciprodinil

La presente invención se refiere a haptenos, conjugados, derivados marcados y anticuerpos para ciprodinil. Así mismo, la presente invención también se refiere al uso de conjugados de ciprodinil como antígenos de ensayo o inmunógenos para obtener anticuerpos de este fungicida; y al uso de los derivados marcados de ciprodinil como antígenos de ensayo. Además, la presente invención también se refiere a un método de análisis de ciprodinil utilizando los anticuerpos obtenidos, en ocasiones junto con antígenos de ensayo que son conjugados o derivados marcados. Esta invención también proporciona un kit para analizar ciprodinil que comprende anticuerpos de este fungicida, en ocasiones junto con antígenos de ensayo que son conjugados o derivados marcados.Peer reviewedConsejo Superior de Investigaciones Científicas (España), Universitata de ValenciaA1 Solicitud de patente con informe sobre el estado de la técnic

Forchlorfenuron-mimicking haptens: From immunogen design to antibody characterization by hierarchical clustering analysis

To obtain highly-specific and selective forchlorfenuron binders, a collection of functionalized derivatives with different spacer arm locations and lengths was prepared. By immunization with target-mimicking haptens, a large battery of monoclonal and polyclonal antibodies against this synthetic cell regulator was produced and exhaustively characterized in two immunoassay formats using homologous and heterologous conjugates. Antibodies with IC50 values lower than 0.3 nM were successfully raised from the prepared immunogens, thus evidencing the efficacy of the explored strategies. In order to identify significant epitopes in the antibody-antigen interaction, a series of new chemical forchlorfenuron analogues, with slight modifications at both rings of the target molecule, were synthesized and evaluated in competitive assays. As a novel approach in hapten recognition studies, data processing was performed by computational classification methods based on hierarchical clustering. This strategy was shown to be highly valuable for a straightforward profiling of antibodies according to analogue recognition patterns. A relationship could be established between the antigen binding properties of antibodies and the structure of the immunogen. Whereas antibodies with equivalent affinities had been obtained from all of the derivatives, their specificity was found to be largely influenced by the differential exposition of the molecule to the immune system.This work was supported by Ministerio de Educación y Ciencia (AGL2009-12940-C02/01/02/ALI), and cofinanced by FEDER Funds. C.S.P. and J.V.M. were hired by the CSIC, the former under a predoctoral I3P contract and the latter under a Ramón y Cajal postdoctoral contract.Peer Reviewe

Derivados funcionalizados e inmunorreactivos para el fungicida fludioxonil

La presente invención se refiere a haptenos, conjugados, derivados marcados y anticuerpos para fludioxonil. Asímismo, la presente invención también se refiere al uso de conjugados de fludioxonil como antígenos de ensayo o inmunógenos para obtener anticuerpos de este fungicida; y al uso de los derivados marcados de fludioxonil como antígenos de ensayo. Además, la presente invención también se refiere a un método de análisis de fludioxonil utilizando los anticuerpos obtenidos, en ocasiones junto con antígenos de ensayo que son conjugados o derivados marcados. Esta invención también proporciona un kit para analizar fludioxonil que comprende anticuerpos de este fungicida, en ocasiones junto con antígenos de ensayo que son conjugados o derivados marcadosPeer reviewedConsejo Superior de Investigaciones Científicas, Universitat de ValènciaA1 Solicitud de patente con informe sobre el estado de la técnic

Derivados funcionalizados e inmunorreactivos para el fungicida fludioxonil

La presente invención se refiere a haptenos, conjugados, derivados marcados y anticuerpos para fludioxonil. Asímismo, la presente invención también se refiere al uso de conjugados de fludioxonil como antígenos de ensayo o inmunógenos para obtener anticuerpos de este fungicida; y al uso de los derivados marcados de fludioxonil como antígenos de ensayo. Además, la presente invención también se refiere a un método de análisis de fludioxonil utilizando los anticuerpos obtenidos, en ocasiones junto con antígenos de ensayo que son conjugados o derivados marcados. Esta invención también proporciona un kit para analizar fludioxonil que comprende anticuerpos de este fungicida, en ocasiones junto con antígenos de ensayo que son conjugados o derivados marcadosPeer reviewedConsejo Superior de Investigaciones Científicas, Universitat de ValènciaB1 Patente sin examen previ

Immunoassays for pyraclostrobin analysis in processed food products using novel monoclonal antibodies and QuEChERS-based extracts

Strobilurins are a family of synthetic natural-derived pesticides widely used for fungi control in many crops. As part of a larger research project, a collection of monoclonal antibodies to one of the most relevant strobilurins, i.e. pyraclostrobin, has been generated using functionalized haptens with the spacer arm located at different sites. The toxophore aliphatic moiety, as observed with other strobilurins, and the planar aromatic two-ring system characteristic of this molecule were revealed as the best tethering sites for high-affinity monoclonal antibody production. A central derivatization position did not generate a good immune response, but such derivatives were useful as heterologous competitors in order to improve assay sensitivity. Direct and indirect assays were characterized in terms of solvent influence, pH, and ionic strength. Immunoassays with limits of detection below 0.1 οg/L were developed. A QuEChERS-based procedure was applied to the extraction of blueberry, strawberry, raspberry, peach, apricot, and plum jams. Clean acetonitrile extracts were properly diluted in water and analyzed by both optimized immunoassays with good accuracy and precision at levels covering the European maximum residue limits for those fruits. © 2012 Elsevier Ltd.This work was supported by Ministerio de Educación y Ciencia (AGL2006-12750-C02-01/02/ALI) and by FEDER funds. J.V.M. was hired by the CSIC under a Ramón y Cajal contract financed by Ministerio de Ciencia e Innovación and the European Social Fund.Peer Reviewe

Site-heterologous haptens and competitive monoclonal antibody-based immunoassays for pyrimethanil residue analysis in foodstuffs

Pyrimethanil is a widely used post-harvest fungicide whose residues are commonly found in fruits and vegetables. We herein report the synthesis of two new functionalized derivatives of pyrimethanil carrying an equivalent spacer arm at different positions of the molecule. The influence of the linker tethering site on the affinity of monoclonal antibodies was shown. Moreover, the development of competitive immunoassays in different formats and with high sensitivity to the target analyte - IC50 values below 0.3μg/L - is described. Optimized assays were characterized by the determination of the limit of quantification, trueness, and precision using water-diluted QuEChERS extracts of fruits and vegetables fortified with pyrimethanil. Finally, in-field treated and blind spiked strawberry, tomato, and cucumber samples were analyzed by the developed immunoassays and a reference chromatographic method. Using Deming regression analysis, we show that results from both methodologies were statistically comparable.This work was supported by the Spanish Ministerio de Ciencia e Innovación (AGL2009-12940-C02-01-02/ALI) and cofinanced by FEDER funds. J.V.M. and F.A.E.-T. were hired by the Consejo Superior de Investigaciones Científicas (CSIC), the former under a Ramón y Cajal contract and the latter under a JAE-doc contract, both of them financed by Ministerio de Ciencia e Innovación and the European Social Fund.Peer Reviewe

Derivados funcionalizados e inmunorreactivos para el fungicida fludioxonil

La presente invención se refiere a haptenos, conjugados, derivados marcados y anticuerpos para fludioxonil. Asímismo, la presente invención también se refiere al uso de conjugados de fludioxonil como antígenos de ensayo o inmunógenos para obtener anticuerpos de este fungicida; y al uso de los derivados marcados de fludioxonil como antígenos de ensayo. Además, la presente invención también se refiere a un método de análisis de fludioxonil utilizando los anticuerpos obtenidos, en ocasiones junto con antígenos de ensayo que son conjugados o derivados marcados. Esta invención también proporciona un kit para analizar fludioxonil que comprende anticuerpos de este fungicida, en ocasiones junto con antígenos de ensayo que son conjugados o derivados marcadosPeer reviewedConsejo Superior de Investigaciones Científicas, Universitat de ValènciaB1 Patente sin examen previ

Fungicide multiresidue monitoring in international wines by immunoassays

24 pages, 5 figures, 1 table. -- Available online 10 November 2015.Azoxystrobin, boscalid, cyprodinil, fenhexamid, and pyrimethanil are new generation fungicides extensively employed in order to combat diseases affecting vineyards worldwide. Owing to their physico-chemical characteristics, residues of these compounds on grapes are transferred to must and wine. In this study, a survey of the occurrence of these fungicides in international wines was carried out by using rapid antibody-based assays. Results are discussed as a function of wine type and sample geographical origin. 44.4% of the samples contained at least one of the targets (>10 μg L−1). Fungicide residue occurrences were 22.4%, 19.2%, 18.8%, 6.8%, and 1.2% for pyrimethanil, boscalid, fenhexamid, cyprodinil, and azoxystrobin, respectively, while residue contents higher than 100 μg L−1 were found in 8.4% of the samples. This study shows that contamination of commercial wines with pesticides is an issue of worldwide relevance with potential implications for consumer health and international trade.This work was supported by the Spanish Ministerio de Ciencia e Innovación (AGL2009-12940-C02-01-02/ALI and AGL2012-39965-C02-01-02/ALI) and cofinanced by FEDER funds.Peer reviewe

English Is It! (ELT Training Series). Vol. 5

English Is It! (ELT Training Series) was created with a view to providing opportunities which can make up, somehow, for this gap. The aforementioned members are the permanent teaching staff in the group, they investigate their different areas of expertise in their classes, expose them to the group and make proposals, which are later turned into articles