Person: Urraca Ruiz, Javier
Loading...
First Name
Javier
Last Name
Urraca Ruiz
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Ciencias Químicas
Department
Química Analítica
Area
Química Analítica
Identifiers
3 results
Search Results
Now showing 1 - 3 of 3
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 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 Eu(III)-Templated molecularly imprinted polymer used as a luminescent sensor for the determination of tenuazonic acid mycotoxin in food samples(Sensors and Actuators B: Chemical, 2021) Rico Yuste, Alberto; Abouhany, Rahma; Urraca Ruiz, Javier; Descalzo López, Ana Belén; Orellana Moraleda, Guillermo; Moreno Bondi, María CruzTenuazonic acid (TeA) is a common mycotoxin produced by Alternaria species found in various foodstuffs. Herein, we describe the preparation of porous molecularly imprinted polymer (MIP) microspheres doped with Eu(III), for selective fast analysis of TeA in rice extracts. The TeA template, bearing a β-diketone moiety, is a good Eu(III)-chelating antenna ligand that can be selectively captured in the MIP cavities and detected by observing the “turned-on” sensitized luminescence of the Eu(III) ions at 615 nm (λex 337 nm). A MIP library was prepared at small scale using diethyl allylmalonate (DEAM) or allyl acetoacetate as functional monomers, mixed in different mole ratios with the template and ethylene glycol dimethacrylate (EDMA) as cross-linker. The screening allowed selection of poly(DEAM-co-EDMA) with Eu(III) as luminogenic metal center for the sensor development. Under the optimized conditions, a linear response to TeA in the 1.7–20 μg mL−1 range, with a detection limit of 0.5 μg mL−1, was obtained. The Eu(III)-doped MIP for TeA showed very little or no cross-recognition of other mycotoxins present in foodstuff such as alternariol, β-zearalenol and cyclopiazonic acid, even containing the same recognition moiety. The MIP-based optosensor was successfully applied to the analysis of rice extracts spiked with TeA, and the results were confirmed by HPLC-DAD.