Person: Benito Peña, María Elena
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First Name
María Elena
Last Name
Benito Peña
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Químicas
Department
Química Analítica
Area
Química Analítica
Identifiers
9 results
Search Results
Now showing 1 - 9 of 9
- Project number: 253
Item Material docente interactivo en inglés para la enseñanza práctica y el autoaprendizaje de (bio)sensores químicos ópticos en Grado y Máster(2018) Descalzo López, Ana Belén; Orellana Moraleda, Guillermo; Moreno Bondi, María Cruz; Benito Peña, María Elena; Urraca Ruiz, JavierMaterial docente (guiones de prácticas, vídeos, cuestionarios multi-respuesta) en inglés para asignaturas de Grado y Máster relacionadas con el tema de sensores (bio)químicos ópticos y la preparación de nanomateriales aplicados en sensores ópticos Item Homogeneous quenching immunoassay for fumonisin B1 based on gold nanoparticles and an epitope-mimicking yellow fluorescent protein(ACS Nano, 2018) Peltomaa, Riikka Johanna; Amaro Torres, Francisco; Carrasco, Sergio; Orellana Moraleda, Guillermo; Benito Peña, María Elena; Moreno Bondi, María CruzHomogeneous immunoassays represent an attractive alternative to traditional heterogeneous assays due to their simplicity, sensitivity, and speed. On the basis of a previously identified epitope-mimicking peptide, or mimotope, we developed a homogeneous fluorescence quenching immunoassay based on gold nanoparticles (AuNPs) and a recombinant epitope-mimicking fusion protein for the detection of mycotoxin fumonisin B1 (FB1). The fumonisin mimotope was cloned as a fusion protein with a yellow fluorescent protein that could be used directly as the tracer for FB1 detection without the need of labeling or a secondary antibody. Furthermore, owing to the fluorescence quenching ability of AuNPs, a homogeneous immunoassay could be performed in a single step without washing steps to separate the unbound tracer. The homogeneous quenching assay showed negligible matrix effects in 5% wheat extract and high sensitivity for FB1 detection, with a dynamic range from 7.3 to 22.6 ng/mL, a detection limit of 1.1 ng/mL, and IC50 value of 12.9 ng/mL, which was significantly lower than the IC50 value of the previously reported assay using the synthetic counterpart of the same mimotope in a microarray format. The homogeneous assay was demonstrated to be specific for fumonisins B1 and B2, as no significant cross-reactivity with other mycotoxins was observed, and acceptable recoveries (86% for FB1 2000 μg/kg and 103% for FB1 4000 μg/kg), with relative standard deviation less than 6.5%, were reported from spiked wheat samples, proving that the method could provide a valuable tool for simple analysis of mycotoxin-contaminated food samples.Item Biosensing Based on Nanoparticles for Food Allergens Detection(Sensors, 2018) Gómez Arribas, Lidia Nazaret; Benito Peña, María Elena; Hurtado Sánchez, María del Carmen; Moreno Bondi, María CruzFood allergy is one of the major health threats for sensitized individuals all over the world and, over the years, the food industry has made significant efforts and investments to offer safe foods for allergic consumers. The analysis of the concentration of food allergen residues in processing equipment, in raw materials or in the final product, provides analytical information that can be used for risk assessment as well as to ensure that food-allergic consumers get accurate and useful information to make their food choices and purchasing decisions. The development of biosensors based on nanomaterials for applications in food analysis is a challenging area of growing interest in the last years. Research in this field requires the combined efforts of experts in very different areas including food chemistry, biotechnology or materials science. However, the outcome of such collaboration can be of significant impact on the food industry as well as for consumer’s safety. These nanobiosensing devices allow the rapid, selective, sensitive, cost-effective and, in some cases, in-field, online and real-time detection of a wide range of compounds, even in complex matrices. Moreover, they can also enable the design of novel allergen detection strategies. Herein we review the main advances in the use of nanoparticles for the development of biosensors and bioassays for allergen detection, in food samples, over the past few years. Research in this area is still in its infancy in comparison, for instance, to the application of nanobiosensors for clinical analysis. However, it will be of interest for the development of new technologies that reduce the gap between laboratory research and industrial applications.Item Desarrollo y validación de métodos analíticos basados en nuevos elementos de reconocimiento molecular para la determinación de antibióticos -Lactámicos en muestras de interés agroalimentario y medioambiental(2007) Benito Peña, María Elena; Moreno Bondi, María CruzEsta Tesis Doctoral se ha realizado en el marco de un Proyecto del V Programa Marco, subvencionado por la Unión Europea dentro del área de Calidad de Vida y Gestión de Recursos Vivos, titulado "Cartridges with molecularly imprinted recognition elements for antibiotic residues monitoring in milk": CREAM (Ref. QLK-1999-00902). La investigación realizada en el marco de la tesis presentada se puede resumir en los siguientes puntos: 1. Caracterización foto física y fotoquímica de los derivados fluorescentes de penicilinas para su aplicación en el análisis de antibióticos. 2. Desarrollo de un fluoro ensayo competitivo, basado en el empleo de mips, como elementos de reconocimiento selectivo para el análisis de antibióticos de la familia de penicilinas en alimentos y medicamentos. 3. Desarrollo de un fluoroinmunoensayo competitivo, totalmente automatizado, basado en el empleo de los derivados fluorescentes de penicilinas y anticuerpos poli clónales selectivos a antibióticos -lacta micos. Aplicación del biosensor al análisis de muestras de leche y medioambientales. 4. Desarrollo de un método cromatográfico basado en la técnica de HPLC con detección UV para la determinación de los residuos de antibióticos -lacta micos (amoxicilina, ampicilina, penicilina G, penicilina V, oxacilina, cloxacilina, nafcilina y dicloxacilina) en muestras biológicas y medioambientales con el fin de validar los dispositivos desarrollados. Este objetivo incluye la optimización de un método de extracción en fase sólida (SPE) para la preconcentración y limpieza de las muestras seleccionadas.Item Highly fluorescent magnetic nanobeads with a remarkable stokes shift as labels for enhanced detection in immunoassays(Small, 2018) Salis, Francesca; Descalzo López, Ana Belén; Benito Peña, María Elena; Moreno Bondi, María Cruz; Orellana Moraleda, GuillermoFluorescence immunoassays are popular for achieving high sensitivity, but they display limitations in biological samples due to strong absorption of light, background fluorescence from matrix components, or light scattering by the biomacromolecules. A powerful strategy to overcome these problems is introduced here by using fluorescent magnetic nanobeads doped with two boron-dipyrromethane dyes displaying intense emission in the visible and near-infrared regions, respectively. Careful matching of the emission and absorption features of the dopants leads to a virtual Stokes shift larger than 150 nm achieved by an intraparticle Förster resonance energy transfer (FRET) process between the donor and the acceptor dyes. Additionally, the magnetic properties of the fluorescent beads allow preconcentration of the sample. To illustrate the usefulness of this approach to increase the sensitivity of fluorescence immunoassays, the novel nanoparticles are employed as labels for quantification of the widely used Tacrolimus (FK506) immunosuppressive drug. The FRET-based competitive inhibition immunoassay yields a limit of detection (LOD) of 0.08 ng/mL, with a dynamic range (DR) of 0.15–2.0 ng/mL, compared to a LOD of 2.7 ng/mL and a DR between 4.1 and 130 ng/mL for the immunoassay carried out with direct excitation of the acceptor dye.Item Tag-specific affinity purification of recombinant proteins by using molecularly imprinted polymers(Analytical Chemistry, 2019) Gómez-Arribas, Lidia N.; Urraca Ruiz, Javier; Benito Peña, María Elena; Moreno Bondi, María CruzEpitope tagging is widely used to fuse a known epitope to proteins for which no affinity receptor is available by using recombinant DNA technology. One example is FLAG epitope (DYKDDDDK), which provides better purity and recoveries than the favorite polyhistidine tag. However, purification requires using anti-FLAG antibody resins, the high cost and non-reusability of which restrict widespread use. One cost-effective solution is provided by the use of bioinspired anti-FLAG molecularly imprinted polymers (MIPs). This work describes the development of MIPs, based on the epitope approach, synthesized from the tetrapeptide DYKD as template that affords purification of FLAG-derived recombinant proteins. Polymer was optimized by using a combinatorial approach to select the functional monomer(s) and cross-linker(s), resulting in the best specific affinity toward FLAG and the peptide DYKD. The imprinted resin obtained was used to purify mCherry proteins tagged with either FLAG or DYKD epitopes from crude cell lysates. Both mCherry variants were highly efficiently purified (R ≥ 95%, RSD ≤ 15%, n = 3) and impurities were removed. Unlike existing antibody-based resins, the proposed tag-imprinting strategy provides a general method for meeting the growing demand for efficient, inexpensive, and versatile materials for tagged proteins purification.Item Optical Biosensors for Label-Free Detection of Small Molecules(Sensors, 2018) Peltomaa, Riikka Johanna; Glahn Martínez, Ana Bettina; Benito Peña, María Elena; Moreno Bondi, María CruzLabel-free optical biosensors are an intriguing option for the analyses of many analytes, as they offer several advantages such as high sensitivity, direct and real-time measurement in addition to multiplexing capabilities. However, development of label-free optical biosensors for small molecules can be challenging as most of them are not naturally chromogenic or fluorescent, and in some cases, the sensor response is related to the size of the analyte. To overcome some of the limitations associated with the analysis of biologically, pharmacologically, or environmentally relevant compounds of low molecular weight, recent advances in the field have improved the detection of these analytes using outstanding methodology, instrumentation, recognition elements, or immobilization strategies. In this review, we aim to introduce some of the latest developments in the field of label-free optical biosensors with the focus on applications with novel innovations to overcome the challenges related to small molecule detection. Optical label-free methods with different transduction schemes, including evanescent wave and optical fiber sensors, surface plasmon resonance, surface-enhanced Raman spectroscopy, and interferometry, using various biorecognition elements, such as antibodies, aptamers, enzymes, and bioinspired molecularly imprinted polymers, are reviewed.Item Improved performance of SPR sensors by a chemical etching of tapered optical fibers(Optics and Lassers in Engineering, 2011) Díaz Herrera, Natalia; Esteban Martínez, Óscar; Navarrete Fernández, María Cruz; González Cano, Agustín; Benito Peña, María Elena; Orellana Moraleda, GuillermoWe present the results of a chemical attack on the optical fiber surface previous to the deposition of the double layer (metal plus dielectric) in Double-layer uniform-waist tapered fibers (DLUWTs) used for the development of SPR sensors. It is shown how this simple chemical treatment increases the roughness of the surface and permits improvement of the stability of the deposits and the general performance of the sensors. The obtained devices are robust and very compact, their sensitivity is good and repeatability of the measurements is remarkably increased. The procedure can be useful for any fiber-optic sensor.Item Sensitive rapid fluorescence polarization immunoassay for free mycophenolic acid determination in human serum and plasma(Analytical Chemistry, 2018) Glahn Martínez, Ana Bettina; Benito Peña, María Elena; Salis, Francesca; Descalzo López, Ana Belén; Orellana Moraleda, Guillermo; Moreno Bondi, María CruzIn this Article, we describe a fluorescence polarization immunoassay (FPIA) using a new label-near infrared fluorescent dye. The developed FPIA method was optimized for the rapid analysis of free mycophenolic acid (MPA) in plasma of transplanted patients. The approach is based on the fluorescence competitive assay between the target immunosuppressant and a novel emissive near-infrared fluorescent dye-tagged MPA and MPA-AO for the binding sites of the anti-MPA antibody. The fluorescent analogue of MPA exhibits emission at 654 nm upon excitation at 629 nm (λexcmax) and shows a good photochemical stability and a significant emission quantum yield (0.16) in phosphate buffer media. Free mycophenolic acid was isolated from blood or plasma samples using ultrafiltration prior to analysis. The sample was incubated for 20 min with 5 μg/mL of anti-MPA antibody and 1 nM of MPA-AO before the measurements. The developed FPIA displays a limit of detection of 0.8 ng/mL (10% binding inhibition) and a dynamic range of 1.7−39 ng/mL (20%−80% binding inhibition) in a PBST buffer, fitting the therapeutic requirements. The immunoassay selectivity was evaluated by measuring the cross-reactivity to other immunosuppressive drugs administered in combination with MPA (cyclosporin A and tacrolimus), as well as for the metabolite MPA glucuronide. The assay has been successfully applied to the analysis of free MPA in the blood of a heart-transplanted patient after oral administration of both mycophenolate mofetil (MMF) and tacrolimus, and the results have been compared with those obtained by rapid-resolution liquid chromatography with diode array detection (RRLC-DAD).