Person: Navarro Villoslada, Fernando
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First Name
Fernando
Last Name
Navarro Villoslada
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Químicas
Department
Química Analítica
Area
Química Analítica
Identifiers
6 results
Search Results
Now showing 1 - 6 of 6
Item Simultaneous determination of zearalenone and alternariol mycotoxins in oil samples using mixed molecularly imprinted polymer beads(Food Chemistry, 2023) Moya-Cavas, Tamara; Navarro Villoslada, Fernando; Urraca Ruiz, Javier; Antonio Serrano, Luis; Orellana Moraleda, Guillermo; Moreno-Bondi, María Cruz; Moreno Bondi, María CruzThis work reports the optimization of a method using Molecularly Imprinted Polymers (MIPs) for the simultaneous determination of zearalenone and alternariol mycotoxins. The method was optimized using a chemometric approach where in the optimized conditions, the cartridges with a mixture (50:50, w/w) of both MIPs, were loaded with 30 mL of sample, washed with 2 mL of ACN/water (20/80, v/v) and eluted with 2.5 mL of trifluoroacetic acid/MeOH (3/97, v/v). The extracts were analyzed by HPLC coupled to a fluorescence detector (FLD). The optimized method has been applied and validated to the analysis of the mycotoxins in maize, sunflower and olive oils samples with a limit of detection of 5 and 2 μg kg- 1, respectively. Recoveries were in the range of 94 % to 108 % (RSD < 6 %) for zearalenone and 92 % to 113 % (RSD < 5 %) for alternariol. The results were confirmed by HPLC-MS/MS.Item Fast and straightforward synthesis in molecular imprinting: core–shell polymerization of magnetic imprinted polymers by microwave induction(ACS Applied Polymer Materials, 2024) Guadaño-Sánchez, Miriam; Navarro Villoslada, Fernando; Delgado-Soria, Guiomar; Marco, José F.; Saura Múzquiz, Matilde; Álvaro-Gómez, Laura; Presa Muñoz De Toro, Patricia Marcela De La; Pérez García, Lucas; Lucas Urraca, JavierIn this work, we report a simple and effective approach for preparing molecular imprint polymer (MIP) coatings directly on magnetic multicore (MMC) iron oxide nanoparticles using a microwave reactor to trigger the polymerization reaction. The nanoparticles were manufactured using a microwave reactor, and the MIPs were synthesized with rhodamine 6G (R6G) as the template molecule, methacrylic acid as the functional monomer, and ethylene glycol dimethacrylate as the cross-linker. The produced MMCs and MMC-MIPs were extensively characterized by analysis of powder X-ray diffraction data, Fourier transform infrared spectra, Mossbauer spectroscopy, SQUID magnetometry, and transmission electron microscopy (TEM). The results show the effective formation of the polymeric layer on the surface of the MMCs, without alteration of the structure or physical properties of the core magnetic nanoparticles. The synthesized MIPs presented a high efficiency in the imprinting process of the MMC-MIPs and high selectivity (MIP R6G, Ka = 7.31 × 10–2 M–1 y, 𝑁¯= 14.14 μmol g–1) toward the target molecule R6G.Item Mycotoxin extraction from edible insects with natural deep eutectic solvents: a green alternative to conventional methods(Journal of Chromatography A, 2021) Prádanas González, Fernando; Álvarez-Rivera, Gerardo; Benito Peña, María Elena; Navarro Villoslada, Fernando; Cifuentes, Alejandro; Herrero, Miguel; Moreno Bondi, María CruzEdible insects are widely consumed in Africa, Asia, Oceania and Latin America, but less commonly so in Western countries. Since the turn of the millennium, however, entomophagy has aroused growing interest worldwide in response to the increasing scarcity of food resources. In fact, edible insects can be a source of high-quality protein, and also of fat, energy, minerals and vitamins. However, the lack of regulatory guidelines for microbiologically or chemically hazardous agents potentially present in these new foods (e.g., mycotoxins) may make their consumption unsafe. In this work, we developed an environmentally friendly analytical method using natural deep eutectic solvents (NADES or natural DES) in combination with ultra-high performance liquid chromatography/tandem mass spectrometry (UHPLC-MS/MS) for the simultaneous determination of six mycotoxins of great concern owing to their toxic effects on humans and animals (namely, fumonisin B 1 , fumonisin B 2 , T-2 toxin, HT-2 toxin, ochratoxin A and mycophenolic acid) in insect-based food products. The target mycotoxins were co-extracted from cricket flour by using the optimum DES composition (namely, a mixture of choline chloride and urea, in a 1:2 mole ratio, containing 15% water which resulted in the highest extraction recoveries for all toxins). An experimental design method (Fractional Factorial Design (FFD) was used to examine the influence of the operational variables DES volume and water content, amount of sample, extraction time and extraction temperature on the extraction efficiency for each mycotoxin. Under optimum conditions, extraction recoveries were close to 100% except for fumonisin B 2 (70%) and T-2 toxin (50%), with relative standard deviations (RSDs) below 13% in all cases. The proposed NADES-UHPLC–MS/MS method was validated in accordance with the European Commission 2002/657/EC and 2006/401/EC decisions, and used to determine the target compounds in cricket flour, silkworm pupae powder and black cricket powder.Item Magnetic microbeads-based amperometric immunoplatform for the rapid and sensitive detection of N6-methyladenosine to assist in metastatic cancer cells discrimination(Biosensors and Bioelectronics, 2021) Povedano Muñumel, Eloy; Gamella Carballo, María; Torrente Rodríguez, Rebeca Magnolia; Montero-Calle, Ana; Pedrero Muñoz, María; Solís-Fernández, Guillermo; Navarro Villoslada, Fernando; Barderas, Rodrigo; Campuzano Ruiz, Susana; Pingarrón Carrazón, José ManuelThis work describes the preparation of an immunoplatform for the sensitive and selective determination of N6-methyladenosine (m6A). The simple and fast protocol involves for the first time the use of micromagnetic immunoconjugates to establish a direct competitive assay between the m6A target and a biotinylated RNA oligomer bearing a single m6A enzymatically labelled with a commercial conjugate of streptavidin-peroxidase (Strep-HRP) as tracer. The cathodic current change measured in the presence of H2O2/hydroquinone (HQ) at screen-printed carbon electrodes (SPCEs) upon surface capturing the magnetic bioconjugates is inversely proportional to the m6A target concentration. After evaluating the effect of key variables, the analytical characteristics were established for the determination of three different targets: the N6-methyladenosine-5′ -triphosphate (m6ATP) ribonucleotide, a short synthetic RNA oligomer bearing a single m6A and the positive control provided in a commercial colorimetric kit for m6A-RNA quantification. The obtained results show that this immunoplatform is competitive with other methods reported to date, achieving an improved sensitivity (limit of detection of 0.9 pM for the short synthetic oligomer) using a much simpler and faster protocol (~1 h) and disposable electrodes for the transduction. Furthermore, the applicability for discriminating the metastatic potential of cancer cells by directly analyzing a small amount of raw total RNA without enriching or fragmenting was also preliminary assessed.Item The ultratrace determination of fluoroquinolones in river water samples by an online solid-phase extraction method using a molecularly imprinted polymer as a selective sorbent(Molecules, 2022) Baeza, Ana; Urriza-Arsuaga, Idoia; Navarro Villoslada, Fernando; Urraca Ruiz, JavierFluoroquinolones (FQs) are broad-spectrum antibiotics widely used to treat animal and human infections. The use of FQs in these activities has increased the presence of antibiotics in wastewater and food, triggering antimicrobial resistance, which has severe consequences for human health. The detection of antibiotics residues in water and food samples has attracted much attention. Herein, we report the development of a highly sensitive online solid-phase extraction methodology based on a selective molecularly imprinted polymer (MIP) and fluorescent detection (HPLC-FLD) for the determination of FQs in water at low ng L−1 level concentration. Under the optimal conditions, good linearity was obtained ranging from 0.7 to 666 ng L−1 for 7 FQs, achieving limits of detection (LOD) in the low ng L−1 level and excellent precision. Recoveries ranged between 54 and 118% (RSD < 17%) for all the FQs tested. The method was applied to determining FQs in river water. These results demonstrated that the developed method is highly sensitive and selective.Item Extracting mycotoxins from edible vegetable oils by using green, ecofriendly deep eutectic solvents(Food Chemistry, 2023) Prádanas González, Fernando; Aragoneses-Cazorla, Rubén; Merino-Sierra, Miguel Angel; Andrade-Bartolomé, Elena; Navarro Villoslada, Fernando; Benito Peña, María Elena; Moreno Bondi, María CruzIn this work, we developed an environmentally friendly liquid–liquid microextraction method using a natural deep eutectic solvent in combination with liquid chromatography for the simultaneous determination of four mycotoxins (deoxynivalenol, alternariol, ochratoxin A and zearalenone) in edible vegetable oils. A chemometric approach assessed the effect of the operational parameters on the mycotoxin extraction efficiency. The extracts were analyzed by HPLC coupled with a diode array and fluorescence detector. The optimum NADES composition resulted in the highest extraction recoveries, and it was applied to coextract the target mycotoxins in several types of edible vegetable oils without using hazardous solvents or requiring further clean-up. The limits of detection ranged from 0.07 to 300μg/kg, and recoveries were close to 100%, except for zearalenone(viz. 35%), with relative standard deviations below 9% in all cases. The proposed method was validated following the European Commission 2002/657/EC and 2006/401/EC.