Persona: González Crevillén, Agustín
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agustingcrevillen@ccia.uned.es
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0000-0002-4470-6502
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González Crevillén
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Agustín
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Publicación Disposable Passive Electrochemical Microfluidic Device for Diagnosis of Congenital Disorders of Glycosylation(European Chemical Societies Publishing, 2021-10-25) Sierra, Tania; Henry, Charles S.; González Crevillén, Agustín; Escarpa, AlbertoA disposable pump-free electrochemical microfluidic device made by using a multilayer lamination technique is proposed for diagnosis of glycosylation disorders. Thanks to the stacking of polyethylene terephthalate (PET) films and double adhesive layers, it is possible to create a geometry that allows the filling of the tailored channels in a fixed time. In the main channel of this passive microfluidic device, the necessary steps to perform the electrochemical determination of transferrin are performed: labeling of the protein with Os (VI) complex (electrochemical tag), washing with water of the osmium residues and electrochemical detection by adsorptive transfer stripping square wave voltammetry. Electrochemical detection released two electrochemical signals: one from Os (VI) complex due to carbohydrates at 0.9 V, and other from the intrinsic electrochemical signal of glycoprotein due to the amino acids at + 0.8 V. The ratio between them establishes an indicator of the degree of glycosylation (called electrochemical index of glycosylation). The method was successfully applied to the analysis of clinical samples from patients with congenital disorders of glycosylation.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 Preclinical Validation of an Electrochemical Sensor for Alcohol Consumption Monitoring in a Polydrug Self-Administration Animal Model(MDPI, 2025-03-08) Garrido Matilla, Lucía; María Hormigos, Roberto; Monago Maraña, Olga; Marcos, Alberto; Ambrosio Flores, Emilio; González Crevillén, AgustínAn electrochemical sensor for identification and monitoring of alcoholism was preclinically validated by analyzing plasma from polydrug-consuming rats (alcohol and cocaine). The sensor measures by adsorptive transfer square wave voltammetry the glycosylation level of transferrin, which is an alcoholism biomarker, through a recently reported parameter called the electrochemical index of glycosylation (EIG). Three rat groups were designed: saline group, cocaine group, and cocaine–alcohol group. Moreover, two periods of withdrawal were studied, after 2 days and 30 days. The alcohol–cocaine group after 2 days of withdrawal showed significantly lower EIG values (p < 0.1) than the rest of groups and also alcohol–cocaine group after 30 days of withdrawal, so the sensor was able to identify the alcohol consumption in rats and to monitor the recovery of glycosylation level after 30 days of withdrawal, even combined with cocaine. Furthermore, the effect of sex was also considered. Receiver operating characteristic (ROC) curves were developed for each sex and the corresponding cut-off values were determined. The sensor showed a clinical sensitivity of 70% for male and 75% for female, and a specificity of 67% for both sexes. This preclinical validation demonstrated the possibilities of this sensor for point of care testing of alcoholism, even in cocaine addicts, making it a potential tool for diagnosis and monitoring of alcohol consumption in detox treatments for humans.Publicación Transferrin analysis in wistar rats plasma: Towards an electrochemical point-of-care approach for the screening of alcohol abuse(Elsevier, 2022-06-29) Rodriguez-Hidalgo, Gema; Sierra, Tania; Dortez, Silvia; Marcos, Alberto; Ambrosio, Emilio; González Crevillén, Agustín; Escarpa, AlbertoSimple and low-cost point-of-care testing (POCT) approaches are necessary not only for the diagnosis of alcohol abuse but also for the follow-up of patients during the treatment of alcohol dependence. To advance the development towards these approaches, a disposable screen printed-based electrochemical sensor is proposed for the diagnosis of chronic alcohol abuse. The selected biomarker to be screened (and followed up) was the carbohydrate deficient transferrin (CDT), which was assessed using the parameter “Electrochemical index of glycosylation” (EIG). EIG is defined as the ratio between the signal generated by carbohydrates present in transferrin (Tf) (selectively labeled with an Os(VI) tag) and the signal generated by the electroactive amino acids present in Tf, measured by adsorptive transfer square wave voltammetry (AdTSWV). The electrochemical sensor exhibited a good limit of detection (LOD ≤ 0.7 g L−1) well below the normal range of transferrin in serum (ranging from 2 to 3.6 g L−1). In addition, the diagnostic capabilities of the sensor were evaluated in plasma rats from 31 individuals (16 chronically exposed to alcohol and 15 saline control), yielding a very good clinical sensitivity and specificity (81% and 87%, respectively). These results draw the potential of this approach to be used for POCT of alcohol abuse, making it a useful tool to help therapists/clinicians even patient’s family in the follow-up of alcohol rehabilitation.Publicación Electrochemical sensor for the assessment of carbohydrate deficient transferrin: Application to diagnosis of congenital disorders of glycosilation(Elsevier, 2021-05) Tania Sierra; González Crevillén, Agustín; Escarpa Miguel, Jesús Alberto; https://orcid.org/0000-0002-7302-0948Carbohydrate deficient transferrin (CDT) is used as biomarker of different health problems as, for example, congenital disorders of glycosylation (CDG). We propose a screen-printed-based electrochemical sensor for the determination of carbohydrate deficient transferrin using an Os (VI) tag-based electrochemistry. When transferrin is labeled with Os (VI) complex, it generates two voltammetric signals: one from carbohydrates (electrochemical signal of osmium (VI) complex at -0.9 V/Ag) and one from the amino acids present in glycoprotein (intrinsic electrochemical signal of glycoprotein at +0.8 V/Ag). The relationship between the two analytical signals (carbohydrate signal/protein signal) is an indicator of the degree of glycosylation (electrochemical index of glycosylation), which has shown an excellent correlation (r = 0.990) with the official parameter %CDT obtained by CE-UV. The suitability of this approach was demonstrated by analyzing serum samples from CDG patients.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 Wearable sensor for solar ultraviolet A radiation monitoring based on a basic bismuth nitrate / graphene quantum dots composite(Elsevier, 2025-11-26) María Hormigos, Roberto; Monago Maraña, Olga; Zapardiel Palenzuela, Antonio; González Crevillén, Agustín; Universidad Nacional de Educación a Distancia (UNED)/SantanderUltraviolet A (UV-A) radiation from the Sun is a significant risk factor for skin cancer owing to long-term exposition for outdoor workers. The growing need for wearable health monitoring devices demands real-time UV-A sensors with high analytical performance to avoid skin conditions resulting from prolonged UV-A exposure. In this work, we aimed to develop a novel, power-less, low-cost, long-term-stable, and flexible wearable sensor. Such a sensor is based on basic bismuth nitrate (BBN) covered with graphene quantum dots (GQDs) as a photodetector. BBN@GQD photoelectrical material was produced by a very low-cost pyrolytic procedure in gram-scale quantities on a simple hot plate. GQDs improved photoelectrical activity of BBN, yielding good responsivity of 0.25 mA·W−1 (at 0 V bias, incident light intensity 17 μW·cm−2 and 365 nm wavelength). The combination of BBN@GQD and ITO electrodes provided a very sensitive and selective photodetector (a limit of detection of 1.6 ± 0.6 μW·cm−2 light intensity at 0 V bias for 365 nm UV-A wavelength), better than most current UV-A photodetectors. Its high sensitivity at 0 V bias enables its employment as a functional power-free real-time UV-A monitor device. Moreover, the wearable sensor showed acceptable reproducibility (18.9 % relative standard deviation at 12.5 μW·cm−2 light intensity) and long-term stability (up to 1 month of storage). This work proposes a promising wearable device for UV-A monitoring in an outdoor environment, using a new photosensitive material (BBN@GQD), which offers new opportunities in the development of UV photodetectors.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 Pump-Free Microfluidic Device for the Electrochemical Detection of α1-Acid Glycoprotein(American Chemical Society Publications, 2021-07-05) Tania, Sierra; Jang, Ilhoon; Noviana, Eka; González Crevillén, Agustín; Escarpa, Alberto; S. Henry, Charlesα1-Acid glycoprotein (AGP) is a glycoprotein present in serum, which is associated with the modulation of the immune system in response to stress or injuries, and a biomarker for inflammatory diseases and cancers. Here, we propose a pump-free microfluidic device for the electrochemical determination of AGP. The microfluidic device utilizes capillary-driven flow and a passive mixing system to label the AGP with the Os (VI) complex (an electrochemical tag) inside the main channel, before delivering the products to the electrode surface. Furthermore, thanks to the resulting geometry, all the analytical steps can be carried out inside the device: labeling, washing, and detection by adsorptive transfer stripping square wave voltammetry. The microfluidic device exhibited a linear range from 500 to 2000 mg L–1 (R2 = 0.990) and adequate limit of detection (LOD = 231 mg L–1). Commercial serum samples were analyzed to demonstrate the success of the method, yielding recoveries around 83%. Due to its simplicity, low sample consumption, low cost, short analysis time, disposability, and portability, the proposed method can serve as a point-of-care/need testing device for AGP.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.