Persona: González Crevillén, Agustín
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González Crevillén
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Publicación Cost-effective fully 3D-printed on-drop electrochemical sensor based on carbon black/polylactic acid: a comparative study with screen-printed sensors in food analysis(Springer, 2024) Monago Maraña, Olga; Aouladtayib-Boulakjar, Nadia; Zapardiel Palenzuela, Antonio; García Domínguez, Amabel; Ayllón Pérez, Jorge; Rodríguez Prieto, Álvaro; Claver Gil, Juan; Camacho López, Ana María; González Crevillén, Agustín3D-printing technology allows scientist to fabricate easily electrochemical sensors. Until now, these sensors were designed employing a large amount of material, which increases the cost and decreases manufacturing throughput. In this work, a low-cost 3D-printed on-drop electrochemical sensor (3D-PES) was fully manufactured by fused filament fabrication, minimizing the number of printing layers. Carbon black/polylactic acid filament was employed, and the design and several printing parameters were optimized to yield the maximum electroanalytical performance using the minimal amount of material. Print speed and extrusion width showed a critical influence on the electroanalytical performance of 3D-PES. Under optimized conditions, the fabrication procedure offered excellent reproducibility (RSD 1.3% in working electrode diameter), speed (< 3 min/unit), and costs (< 0.01 $ in material cost). The 3D-PES was successfully applied to the determination of phloridzin in apple juice. The analytical performance of 3D-PES was compared with an equivalent commercial on-drop screen-printed electrode, yielding similar precision and accuracy but lower sensitivity. However, 3D-PES provides interesting features such as recyclability, biodegradability, low-cost, and the possibility of being manufactured near the point of need, some of which meets several demands of Green Chemistry. This cost-effective printing approach is a green and promising alternative for manufacturing disposable and portable electroanalytical devices, opening new possibilities not only in on-site food analysis but also in point-of-care testing.Publicación Untargeted authentication of fruit juices based on electrochemical fingerprints combined with chemometrics. Adulteration of orange juice as case of study(ELSEVIER, 2024) Monago Maraña, Olga; Zapardiel Palenzuela, Antonio; González Crevillén, AgustínThis work presents a novel strategy for authentication of fruit juices. The methodology is based on an electrochemical method combined with chemometrics. In addition, the case of orange juice adulteration with grapefruit juices was studied using this methodology. The electrochemical fingerprint of different juices showed the influence from different polyphenols according to the type of fruit. First, Principal Component Analysis (PCA) was able to differentiate clusters of different juices, being the higher group distance within apple, orange, and grape juices samples. On the other hand, partial least-squares – discriminant analysis (PLS-DA) and PCA-linear discriminant analysis (LDA) were used as classification methods, obtaining better results for orange and apple models. Furthermore, good results were obtained for the authentication of orange juices, compared to other juices, with an error rate of 0.04 for cross-validation. In the case of adulteration of orange juice was detected using PLS-DA at an adulteration level as low as 1%. Regression vectors for all models highlighted identifiable potential values that could be related to the main polyphenols in each type of fruit. This electrochemical method is rapid, low-cost, and compatible with on-site analysis compared to other laborious analysis described in the literature.Publicación Effect of nanocellulose polymorphism on electrochemical analytical performance in hybrid nanocomposites with non‑oxidized single‑walled carbon nanotubes(Springer, 2022-06-14) Dortez, Silvia; Sierra, Tania; Álvarez‑Sánchez, Miguel Á.; González‑Domínguez, José M.; Benito, Ana M.; Maser, Wolfgang K.; González Crevillén, Agustín; Escarpa, AlbertoTwo cellulose nanocrystals/single-walled carbon nanotube (CNC/SW) hybrids, using two cellulose polymorphs, were evaluated as electrochemical transducers: CNC type I (CNC-I/SW) and CNC type II (CNC-II/SW). They were synthesized and fully characterized, and their analytical performance as electrochemical sensors was carefully studied. In comparison with SWCNT-based and screen-printed carbon electrodes, CNC/SW sensors showed superior electroanalytical performance in terms of sensitivity and selectivity, not only in the detection of small metabolites (uric acid, dopamine, and tyrosine) but also in the detection of complex glycoproteins (alpha-1-acid glycoprotein (AGP)). More importantly, CNC-II/SW exhibited 20 times higher sensitivity than CNC-I/SW for AGP determination, yielding a LOD of 7 mg L −1 .These results demonstrate the critical role played by nanocellulose polymorphism in the electrochemical performance of CNC/SW hybrid materials, opening new directions in the electrochemical sensing of these complex molecules. In general, these high-active-surface hybrids smartly exploited the preserved non-oxidized SW conductivity with the high aqueous dispersibility of the CNC, avoiding the use of organic solvents or the incorporation of toxic surfactants during their processing, making the CNC/SW hybrids promising nanomaterials for electrochemical detection following greener approaches.Publicación 3D-printed Transmembrane Glycoprotein Cancer Biomarker Aptasensor(Elsevier, 2021-08-21) González Crevillén, Agustín; Mayorga Martinez, Carmen C.; Zelenka, Jaroslav; Rimpelová, Silvie; Ruml, Tomáš; Pumera, MartinPoint-of-care, easy to manufacture, and low cost detection of cancer biomarkers is crucial for fighting the early stage disease. 3D printing allows delocalized printing at remote locations with updates/upgrades available globally via electronic files. Mucin 1 (MUC1) is a protein that is overexpressed in a number of epithelial cancers and is a key factor in advancement of the disease. Here we show the simple point-of-care 3D printing fabrication of a MUC1 aptasensor using a nanocarbon/polymer filament. Efficacy of the 3D-printed aptasensor is demonstrated by monitoring the expression and release of MUC1 in breast cancer cell cultures. Such a simple, low cost, and easy to locally fabricate cancer biosensor will have a large impact on the field of cancer diagnostics.Publicación Electrochemically Reduced Graphene Oxide-Based Screen-Printed Electrodes for Total Tetracycline Determination by Adsorptive Transfer Stripping Differential Pulse Voltammetry(MDPI, 2019-12-21) S. Lorenzetti, Anabela; Sierra, Tania; Domini, Claudia E.; Lista, Adriana G.; González Crevillén, Agustín; Escarpa, AlbertoDisposable electrochemically reduced graphene oxide-based (ERGO) screen-printed electrodes (SPE) were developed for the determination of total tetracyclines as a sample screening approach. To this end, a selective adsorption-detection approach relied on adsorptive transfer stripping differential pulse voltammetry (AdTDPV) was devised, where the high adsorption capacity and the electrochemical properties of ERGO were simultaneously exploited. The approach was very simple, fast (6 min.), highly selective by combining the adsorptive and the electrochemical features of tetracyclines, and it used just 10 μL of the sample. The electrochemical sensor applicability was demonstrated in the analysis of environmental and food samples. The not-fully explored AdTDPV analytical possibilities on disposable nanostructured transducers become a new tool in food and environmental fields; drawing new horizons for “in-situ” analysis.Publicación Disposable electrochemical sensor combined with molecularly imprinted solid-phase extraction for catabolites detection of flavan-3-ol in urine samples(Elsevier, 2021-07-26) Mora-Granados, M.; González Crevillén, Agustín; González-Gómez D.; Gallego-Picó, A.; https://orcid.org/0000-0002-6167-6106; https://orcid.org/0000-0002-3321-9290Polyphenols are bioactive substances of vegetal origin with a significant impact on human health. The assessment of polyphenol intake and excretion is therefore important. In this work, a new electrochemical approach based on molecularly imprinted polymer extraction and preconcentration, combined with a disposable carbon screen-printed sensor and adsorptive transfer differential pulse voltammetry detection has been proposed for quantifying of 4-hydroxyphenylacetic acid (4-HPA), which is a biomarker of flavan-3-ols intake, and other phenolic acids. The simple experimental performance has allowed the rapid data collection with relevant information about the profile of catabolites extracted. The method was validated over a concentration range of 10–200 mg L−1, R2 > 0.999. In the optimized conditions, the recovery value was 94% with RSD 8%. The limits of detection and quantification were 2.38 mg L−1 and 7.21 mg L−1, respectively. The method was validated by means of a chromatographic method, being the differences between the values of the 4-HPA concentrations obtained by both methods under 1%. The proposed method showed high recoveries, low detection limit, and good accuracy, providing a fast, reliable, and cheap procedure to quantify phenolic metabolites in urine, and representing therefore a good and interesting alternative method. Also, the procedure offers other advantages, including the miniaturization, the low use of organic solvents, the ability to analyse small volumes of samples, in situ analysis and simple instrumentation requirement.Publicación Gold nanostructure-related non-plasmon resonance absorption band as a fingerprint of ortho-alkyl substituted phenolic compounds(Elsevier, 2021-08-29) Silvia Dortez; Maria Cristina González; González Crevillén, Agustín; Alberto EscarpaA systematic study for correlating the chemical structure of phenolic compounds with their capacity to form gold nanoparticles was carried out. Two groups of phenolic compounds were selected: one group with a substituent with different size at ortho position respect to hydroxyl group (phenol, o-cresol, 2-ethylphenol, 2-iso-propylphenol, 2-tert-butylphenol and 2-methoxyphenol); and the second group consists of phenolic compounds with the same substituent (methyl) at different positions respect to hydroxyl group (o-cresol, m-cresol and p-cresol). In addition to the characteristic gold nanoparticles (AuNPs) formation band at 550 nm obtained for all the structures of phenolic compounds studied, ortho-alkyl substituted yielded selectively a metastable band at 400 nm, due to gold nanoclusters (AuNCs) formation. We hypothesized that these specific phenolic compounds can temporally stabilize AuNCs with number of Au atoms ranging from 3 to 41. This new band was proposed for rapid screening of these phenolics with promising results, paving the way to new and more selective colorimetric assay for phenolic compounds determination.Publicación Paper-Based Analytical Devices for Accurate Assessment of Transferrin Saturation in Diagnosed Clinical Samples from Ischemic Stroke Patients(ACS, 2023-07-23) Dortez, Silvia; DeGregorio-Rocasolano, Núria; Millán, Mònica; Gasull, Teresa; González Crevillén, Agustín; Escarpa, AlbertoFor the first time, a paper-based analytical device (PAD) was developed for the assessment of transferrin saturation (TSAT), which is defined as the ratio between iron bound to transferrin (Tf) and the total iron-binding capacity (TIBC) of Tf. Both parameters were simultaneously measured on the same PAD using ferrozine as a chromophore and a smartphone as the color reader. To this end, Tf was first isolated from serum using anti-Tf immunomagnetic beads to ensure that only the Tf-bound iron was measured, improving the selectivity and accuracy of TSAT assessment. To demonstrate the practical utility of the device, it was validated by analyzing a certified reference material, showing excellent accuracy (Er < 4%) and good precision (RSD ≤ 6%). Finally, 18 diagnosed serum samples from ischemic stroke patients were analyzed by this approach, and the results were compared with those obtained by urea-PAGE, showing not only an excellent correlation (r = 0.93, p < 0.05) but that the PAD approach has become statistically identical to the free-interference urea-PAGE. In comparison with the slow, tedious, and non-miniaturized-PAGE, this PAD approach exhibited attractive characteristics such as low cost, disposability, and connectivity, showing great potential for future point-of-care testing, especially in developing countries and/or remote areas, where access to medical or clinical facilities is limited.Publicación A dual colorimetric-electrochemical microfluidic paper-based analytical device for point-of-care testing of ischemic strokes(The Royal Society of Chemistry, 2024-07-29) Dortez, Silvia; Pacheco, Marta; Gasull, Teresa; González Crevillén, Agustín; Escarpa, AlbertoA novel microfluidic paper-based analytical device with dual colorimetric and electrochemical detection (dual μPAD) was developed for the assessment of transferrin saturation (TSAT) in samples from ischemic stroke patients. TSAT was calculated from the ratio between transferrin-bound iron, which was colorimetrically measured, and the total iron-binding capacity, which was electrochemically measured. To this end, a μPAD was smartly designed, which integrated both colorimetric and electrochemical detection reservoirs, communicating via a microchannel acting as a chemical reactor, and with preloading/storing capabilities (reagent-free device). This approach allowed the dual and simultaneous determination of both parameters, providing an improvement in the reliability of the results due to an independent signal principle and processing. The μPADs were validated by analyzing a certified reference material, showing excellent accuracy (Er ≤ 5%) and precision (RSD ≤ 2%). Then they were applied to the analysis of diagnosed serum samples from ischemic stroke patients. The results were compared to those provided by a free-interference method (urea-PAGE). Impressively, both methods exhibited a good correlation (r = 0.96, p < 0.05) and no significant differences were found between them (slope 1.0 ± 0.1 and the intercept 1 ± 4, p < 0.05), demonstrating the excellent accuracy of our approach during the analysis of complex samples from ischemic stroke patients, using just 90 μL of clinical samples and taking less than 90 min in comparison with the 18 hours required by the urea-PAGE approach. The developed fully integrated colorimetric-electrochemical μPAD is a promising ready to use reagent-free device for the point-of-care testing of TSAT, which can be used to assist physicians in the fast diagnosis and prognosis of ischemic strokes, where the decision-time is crucial for the patient's survival.Publicación Electroanalytical paper-based device for reliable detection and quantification of sugars in milk(Elsevier, 2024-01-01) Dortez, Silvia; González Crevillén, Agustín; Escarpa, Alberto; Cinti, StefanoKnowing the level of sugars in food and beverages is essential because they are related to diseases such as diabetes, and obesity, among others. In this regard, an approach has been designed, characterized, and applied to develop the first all-in-one paper-based microfluidic analytical device for the quantification of sugars in milk samples. In particular, the powerful combination of the paper-based platform, the facile manufacturing, and the on-demand customization, allowed to obtain a stand-alone platform that was capable to store all the reagents necessary for the assay, to treating the sample by removing major interferences due to lipids and proteins, and to visualize the results in minutes. A wax-patterned chromatographic paper was finely designed to provide a reagent-free platform for the use of non-specialists applied towards the analysis of sugars' content (lactose as the main sugar). Sugars were electrochemically quantified down to 0.16 g L−1 with a repeatability of 5%. To strengthen the efficacy of the novel platform, the electrochemical paper-based analytical device has been applied to commercial milk, including skimmed, semi-skimmed, whole, and lactose-free, confirming satisfactory performance with analytical reliability. This paper-based architecture opens novel avenues for portable (bio)sensing of other relevant species, not only in the agri-food field.