José Pingarrón - Profile on Academia.edu (original) (raw)
Papers by José Pingarrón
Electroanalysis, 2020
This work reports the first electrochemical immunoassay involving magnetic microbeads (MBs) for t... more This work reports the first electrochemical immunoassay involving magnetic microbeads (MBs) for the determination of galectin-3 (Gal-3), a β-galactosidasebinding lectin that acts as mediator of heart failure (HF). MBs-captured sandwich-type immune complexes and amperometric detection at disposable screen-printed carbon electrodes were used. The immunoplatform showed a detection limit of 8.3 pg mL À 1 , good reproducibility, and excellent selectivity. The endogenous concentration of Gal-3 in human plasma from HF patients was determined with results in agreement with those obtained using ELISA. The multiplexing feasibility of the developed immunoplatform was demonstrated for the simultaneous determination of Gal-3 and N-terminal pro-brain natriuretic peptide (NT-proBNP).
The 24th International Electronic Conference on Synthetic Organic Chemistry, 2021
Rheumatoid arthritis is an autoimmune disorder characterized by persistent erosive synovitis, sys... more Rheumatoid arthritis is an autoimmune disorder characterized by persistent erosive synovitis, systemic inflammation and the presence of autoantibodies, which play an important role in inducing inflammation and joint damage, releasing pro-inflammatory cytokines from monocytes and macrophages . Likewise, neutrophil activating protein-2 (CXCL7) is a platelet-derived growth factor belonging to the CXC chemokine subfamily, which is expressed in serum, synovial fluid and synovial tissue of patients developing rheumatoid arthritis during the first twelve weeks, being useful to reflect local pathological changes . Besides, matrix metalloproteinase-3 (MMP-3), which is induced by inflammatory cytokines such as interleukin-1 (IL-1) and tumor necrosis factor alpha (TNFα) in rheumatoid synovium, degrades several extracellular matrix components of cartilage and plays central roles in rheumatoid joint destruction . Therefore, monitoring serum CXCL7 and MMP-3 levels is useful for predicting the disease activity in rheumatoid arthritis. In this work, the construction and analytical performance of a dual electrochemical platform for the simultaneous determination of CXCL7 and MMP-3 is described. After the optimization of experimental variables involved in the preparation and implementation of the biosensor, the analytical usefulness of the developed configuration was demonstrated by its application to the determination of these biomarkers in serum samples from healthy individuals and patients with rheumatoid arthritis. To carry out the simultaneous determination of CXCL7 and MMP3 in human serum, just a fifty-fold sample dilution in PBS of pH 7.4 was required. In addition, the results obtained using the dual immunosensor were compared with those provided by the respective ELISA immunoassays, yielding no significant differences between the two methods. It is important to highlight that reagents consumption, four times smaller using the dual immunosensor than that required in the ELISA protocol, and an assay time of 2 h 50 min versus almost 5 h, counted in both cases after incubation of the capture antibody, are advantageous features of the dual immunosensor [5].
Different parameters affecting the preparation of the electrochemical biosensor were optimized an... more Different parameters affecting the preparation of the electrochemical biosensor were optimized and the obtained results are shown in figure 3. Fig. 3 Effect of the amount of nanohybrid (a), incubated antibody (b), time of immobilization (c) and coating with 1% BSA (d) on the normalized amperometric signal of the electrode toward 10 3 CFU/ mL Brett. Eapp = −200 mV, 100% relative current intensity = 460 nA Other parameters affecting the measurement of the yeast were optimized as shown figure 4. Fig. 4 Influence o the time (a), and temperature (b) of incubation of the immunosensor with 10 3 CFU/ mL Brett. Eapp = −200 mV, 100% relative current intensity = 460 nA The analytical performance of nanostructures immunosensor was evaluated under these optimal working conditions. This electrode allowed the amperometric detection of B. bruxellensis in buffered solutions and red wine samples in the range of 10-10 6 CFU/mL and 10 2-10 6 CFU/mL, with detection limits of 8 CFU/mL and 56 CFU/mL, resp...
Multiplexed Determination of Fertility‐related Hormones in Saliva Using Amperometric Immunosensing
Electroanalysis, 2021
Special Collection on Bioelectrochemistry
ChemElectroChem, 2019
Biomolecules, 2019
Herein, and in contrast to current production of anti-Zika virus antibodies, we propose a semi-co... more Herein, and in contrast to current production of anti-Zika virus antibodies, we propose a semi-combinatorial virtual strategy to select short peptides as biomimetic antibodies/binding agents for the detection of intact Zika virus (ZIKV) particles. The virtual approach was based on generating different docking cycles of tetra, penta, hexa, and heptapeptide libraries by maximizing the discrimination between the amino acid motif in the ZIKV and dengue virus (DENV) envelope protein glycosylation site. Eight peptides, two for each length (tetra, penta, hexa, and heptapeptide) were then synthesized and tested vs. intact ZIKV particles by using a direct enzyme linked immunosorbent assay (ELISA). As a reference, we employed a well-established anti-ZIKV antibody, the antibody 4G2. Three peptide-based assays had good detection limits with dynamic range starting from 105 copies/mL of intact ZIKV particles; this was one order magnitude lower than the other peptides or antibodies. These three pe...
Sensors, 2017
Rapid and reliable diagnosis of infectious diseases caused by pathogens, and timely initiation of... more Rapid and reliable diagnosis of infectious diseases caused by pathogens, and timely initiation of appropriate treatment are critical determinants to promote optimal clinical outcomes and general public health. Conventional in vitro diagnostics for infectious diseases are time-consuming and require centralized laboratories, experienced personnel and bulky equipment. Recent advances in electrochemical affinity biosensors have demonstrated to surpass conventional standards in regards to time, simplicity, accuracy and cost in this field. The tremendous potential offered by electrochemical affinity biosensors to detect on-site infectious pathogens at clinically relevant levels in scarcely treated body fluids is clearly stated in this review. The development and application of selected examples using different specific receptors, assay formats and electrochemical approaches focusing on the determination of specific circulating biomarkers of different molecular (genetic, regulatory and functional) levels associated with bacterial and viral pathogens are critically discussed. Existing challenges still to be addressed and future directions in this rapidly advancing and highly interesting field are also briefly pointed out.
ACS Omega, 2018
This paper describes a disposable amperometric biosensor for simple and sensitive determination o... more This paper describes a disposable amperometric biosensor for simple and sensitive determination of miRNA-21. The bioplatform consists of gold nanoparticles-nanostructured electrode surfaces on which a direct hybridization assay involving the immobilization of a specific thiolated DNA capture probe and recognition of the formed DNA-miRNA-21 heteroduplex by a specific antibody is implemented. The antibody is further recognized through its Fc region by a commercial bacterial protein containing 40 units of horseradish peroxidase (HRP) (ProtA-polyHRP40). The amperometric detection of the hybridization process using the H 2 O 2 /hydroquinone system allows quantification of the target miRNA in the 0.096-25 pM linear range with a detection limit of 29 fM (0.29 amol in 10 μL of sample). The bioplatform offers excellent selectivity against noncomplementary sequences and very acceptable against sequences with an unpaired base (only 30% of the response obtained for the target miRNA). In addition, the bioplatform was shown to be useful for the determination of the endogenous content of the target oncomiR directly in blood serum from breast cancer patients and in breast cancer cells using only 10 ng of total extracted RNA.
International Journal of Molecular Sciences, 2019
(Bio)fouling processes arising from nonspecific adsorption of biological materials (mainly protei... more (Bio)fouling processes arising from nonspecific adsorption of biological materials (mainly proteins but also cells and oligonucleotides), reaction products of neurotransmitters oxidation, and precipitation/polymerization of phenolic compounds, have detrimental effects on reliable electrochemical (bio)sensing of relevant analytes and markers either directly or after prolonged incubation in rich-proteins samples or at extreme pH values. Therefore, the design of antifouling (bio)sensing interfaces capable to minimize these undesired processes is a substantial outstanding challenge in electrochemical biosensing. For this purpose, efficient antifouling strategies involving the use of carbon materials, metallic nanoparticles, catalytic redox couples, nanoporous electrodes, electrochemical activation, and (bio)materials have been proposed so far. In this article, biomaterial-based strategies involving polymers, hydrogels, peptides, and thiolated self-assembled monolayers are reviewed and critically discussed. The reported strategies have been shown to be successful to overcome (bio)fouling in a diverse range of relevant practical applications. We highlight recent examples for the reliable sensing of particularly fouling analytes and direct/continuous operation in complex biofluids or harsh environments. Opportunities, unmet challenges, and future prospects in this field are also pointed out.
Analytica chimica acta, Jan 29, 2018
A new label-free electrochemical immunosensor is constructed for the selective and sensitive dete... more A new label-free electrochemical immunosensor is constructed for the selective and sensitive determination of the clinically relevant biomarker receptor tyrosine kinase (AXL) in human serum. The disposable immunosensing platform is prepared by immobilization of the specific anti-AXL antibody onto amine functionalized graphene quantum dots (fGQDs)-modified screen-printed carbon electrodes (SPCEs). The affinity reactions were monitored by measuring the decrease in the differential pulse voltammetric (DPV) response of the redox probe Fe(CN). All the experimental variables involved in the preparation of the modified electrodes and in the immunosensor performance were optimized. The as prepared immunosensor exhibits an improved analytical performance with respect to other electrochemical immunosensors reported so far, with a wider range of linearity and a lower detection limit, 0.5 pg mL, which is more than one hundred thousand times lower than the established cut-off value for heart fai...
Sensors (Basel, Switzerland), Jan 15, 2018
This work reports an amperometric biosensor for the determination of miRNA-21, a relevant oncogen... more This work reports an amperometric biosensor for the determination of miRNA-21, a relevant oncogene. The methodology involves a competitive DNA-target miRNA hybridization assay performed on the surface of magnetic microbeads (MBs) and amperometric transduction at screen-printed carbon electrodes (SPCEs). The target miRNA competes with a synthetic fluorescein isothiocyanate (FITC)-modified miRNA with an identical sequence for hybridization with a biotinylated and complementary DNA probe (b-Cp) immobilized on the surface of streptavidin-modified MBs (b-Cp-MBs). Upon labeling, the FITC-modified miRNA attached to the MBs with horseradish peroxidase (HRP)-conjugated anti-FITC Fab fragments and magnetic capturing of the MBs onto the working electrode surface of SPCEs. The cathodic current measured at -0.20 V (versus the Ag pseudo-reference electrode) was demonstrated to be inversely proportional to the concentration of the target miRNA. This convenient biosensing method provided a linear r...
International journal of molecular sciences, Jan 9, 2017
This work describes a sensitive amperometric magneto-biosensor for single-step and rapid determin... more This work describes a sensitive amperometric magneto-biosensor for single-step and rapid determination of microRNAs (miRNAs). The developed strategy involves the use of direct hybridization of the target miRNA (miRNA-21) with a specific biotinylated DNA probe immobilized on streptavidin-modified magnetic beads (MBs), and labeling of the resulting heteroduplexes with a specific DNA-RNA antibody and the bacterial protein A (ProtA) conjugated with an horseradish peroxidase (HRP) homopolymer (Poly-HRP40) as an enzymatic label for signal amplification. Amperometric detection is performed upon magnetic capture of the modified MBs onto the working electrode surface of disposable screen-printed carbon electrodes (SPCEs) using the H₂O₂/hydroquinone (HQ) system. The magnitude of the cathodic signal obtained at -0.20 V (vs. the Ag pseudo-reference electrode) demonstrated linear dependence with the concentration of the synthetic target miRNA over the 1.0 to 100 pM range. The method provided a d...
C, 2017
Nanotechnology is becoming increasingly important in the field of (bio)sensors. The performance a... more Nanotechnology is becoming increasingly important in the field of (bio)sensors. The performance and sensitivity of electrochemical biosensors can be greatly improved by the integration of nanomaterials into their construction. In this sense, carbon nanomaterials have been widely used for preparation of biosensors due to their ability to enhance electron-transfer kinetics, high surface-to-volume ratios, and biocompatibility. Fullerenes are a very promising family of carbon nanomaterials and have attracted great interest in recent years in the design of novel biosensing systems due to fullerenes' exceptional properties. These include multiple redox states, stability in many redox forms, easy functionalization and signal mediation. This paper outlines the state-of-the-art and future directions in the use and functionalization of fullerene-C 60 and its derivatives, both as electrode modifiers and advanced labels in electrochemical catalytic and affinity biosensors through selected applications.
Beverages, 2017
In this work, a new automated bioanalyzer based on the use of enzymatic biosensors as amperometri... more In this work, a new automated bioanalyzer based on the use of enzymatic biosensors as amperometric detectors is reported. This automatic bioanalyzer is configurable both as continuous flow and flow injection analysis systems and enables both on-line and off-line monitoring of ethanol in low-alcohol beer to be performed. The attractive analytical and operational characteristics demonstrated by the automated bioanalyzer make it a promising, simple, rapid, and reliable tool for quality control of this beverage in the beer industry, either during the manufacturing process or in the final product. Moreover its applicability to the analysis of the ethanol content in different non-alcoholic beers working at different modes was successfully demonstrated.
Chemosensors, 2017
Safety and quality are key issues of today's food industry. Since the food chain is becoming more... more Safety and quality are key issues of today's food industry. Since the food chain is becoming more and more complex, powerful analytical methods are required to verify the performance of food safety and quality systems. Indeed, such methods require high sensitivity, selectivity, ability for rapid implementation and capability of automatic screening. Electroanalytical chemistry has, for decades, played a relevant role in food safety and quality assessment, taking more and more significance over time in the solution of analytical problems. At present, the implementation of electrochemical methods in the food is evident. This is in a large part due to the relevant results obtained by combining the attractive advantages of electrochemical transduction strategies (in terms of relatively simple hardware, versatility, interface with automatic logging and feasibility of application outside the laboratory environment) with those from biosensors technology. Important examples of enzyme electrochemical biosensors are those dedicated to the determination of glucose, alcohol or cholesterol are important examples. In addition, other types of different electrochemical biosensing approaches have emerged strongly in the last years. Among these, the strategies involving affinity interactions have been shown to possess a large number of applications. Therefore, electrochemical immunosensors and DNA-based biosensors have been widely used to determine major and minor components in foodstuffs, providing sufficient data to evaluate food freshness, the quality of raw materials, or the origin of samples, as well as to determine a variety of compounds at trace levels related to food safety such as micotoxins, allergens, drugs residues or pathogen microorganisms. This review discusses some critical examples of the latest advances in this area, pointing out relevant methodologies related to the measurement techniques, including the use of nanostructured electrodes and strategies for signal amplification.
C, 2017
Growing demand for developing ultrasensitive electrochemical bioassays has led to the design of n... more Growing demand for developing ultrasensitive electrochemical bioassays has led to the design of numerous signal amplification strategies. In this context, carbon-based nanomaterials have been demonstrated to be excellent tags for greatly amplifying the transduction of recognition events and simplifying the protocols used in electrochemical biosensing. This relevant role is due to the carbon-nanomaterials' large surface area, excellent biological compatibility and ease functionalization and, in some cases, intrinsic electrochemistry. These carbon-based nanomaterials involve well-known carbon nanotubes (CNTs) and graphene as well as the more recent use of other carbon nanoforms. This paper briefly discusses the advantages of using carbon nanostructures and their hybrid nanocomposites for amplification through tagging in electrochemical biosensing platforms and provides an updated overview of some selected examples making use of labels involving carbon nanomaterials, acting both as carriers for signal elements and as electrochemical tracers, applied to the electrochemical biosensing of relevant (bio)markers.
Sensors, 2016
Ultrasensitive biosensing is currently a growing demand that has led to the development of numero... more Ultrasensitive biosensing is currently a growing demand that has led to the development of numerous strategies for signal amplification. In this context, the unique properties of magnetic particles; both of nano-and micro-size dimensions; have proved to be promising materials to be coupled with disposable electrodes for the design of cost-effective electrochemical affinity biosensing platforms. This review addresses, through discussion of selected examples, the way that nano-and micro-magnetic particles (MNPs and MMPs; respectively) have contributed significantly to the development of electrochemical affinity biosensors, including immuno-, DNA, aptamer and other affinity modes. Different aspects such as type of magnetic particles, assay formats, detection techniques, sensitivity, applicability and other relevant characteristics are discussed. Research opportunities and future development trends in this field are also considered.
Chemosensors, 2016
In this work, a novel magnetic beads (MBs)-based immunosensing approach for the rapid and simulta... more In this work, a novel magnetic beads (MBs)-based immunosensing approach for the rapid and simultaneous determination of the main peanut allergenic proteins (Ara h 1 and Ara h 2) is reported. It involves the use of sandwich-type immunoassays using selective capture and detector antibodies and carboxylic acid-modified magnetic beads (HOOC-MBs). Amperometric detection at´0.20 V was performed using dual screen-printed carbon electrodes (SPdCEs) and the H 2 O 2 /hydroquinone (HQ) system. This methodology exhibits high sensitivity and selectivity for the target proteins providing detection limits of 18.0 and 0.07 ng/mL for Ara h 1 and Ara h 2, respectively, with an assay time of only 2 h. The usefulness of the approach was evaluated by detecting the endogenous content of both allergenic proteins in different food extracts as well as trace amounts of peanut allergen (0.0001% or 1.0 mg/kg) in wheat flour spiked samples. The developed platform provides better Low detection limits (LODs) in shorter assay times than those claimed for the allergen specific commercial ELISA kits using the same immunoreagents and quantitative information on individual food allergen levels. Moreover, the flexibility of the methodology makes it readily translate to the detection of other food-allergens.
Electroanalysis : Faster Processing and Greater Service
Electroanalysis, 2016
Secuencia de nucleótido y proteína β-galactosidasa de Streptococcus mitis, procedimiento de obten... more Secuencia de nucleótido y proteína β-galactosidasa de Streptococcus mitis, procedimiento de obtención y sus aplicaciones. 57 Resumen: Secuencia de nucleótido y proteína β-galactosidasa de Streptococcus mitis, procedimiento de obtención y sus aplicaciones.
Electroanalysis, 2020
This work reports the first electrochemical immunoassay involving magnetic microbeads (MBs) for t... more This work reports the first electrochemical immunoassay involving magnetic microbeads (MBs) for the determination of galectin-3 (Gal-3), a β-galactosidasebinding lectin that acts as mediator of heart failure (HF). MBs-captured sandwich-type immune complexes and amperometric detection at disposable screen-printed carbon electrodes were used. The immunoplatform showed a detection limit of 8.3 pg mL À 1 , good reproducibility, and excellent selectivity. The endogenous concentration of Gal-3 in human plasma from HF patients was determined with results in agreement with those obtained using ELISA. The multiplexing feasibility of the developed immunoplatform was demonstrated for the simultaneous determination of Gal-3 and N-terminal pro-brain natriuretic peptide (NT-proBNP).
The 24th International Electronic Conference on Synthetic Organic Chemistry, 2021
Rheumatoid arthritis is an autoimmune disorder characterized by persistent erosive synovitis, sys... more Rheumatoid arthritis is an autoimmune disorder characterized by persistent erosive synovitis, systemic inflammation and the presence of autoantibodies, which play an important role in inducing inflammation and joint damage, releasing pro-inflammatory cytokines from monocytes and macrophages . Likewise, neutrophil activating protein-2 (CXCL7) is a platelet-derived growth factor belonging to the CXC chemokine subfamily, which is expressed in serum, synovial fluid and synovial tissue of patients developing rheumatoid arthritis during the first twelve weeks, being useful to reflect local pathological changes . Besides, matrix metalloproteinase-3 (MMP-3), which is induced by inflammatory cytokines such as interleukin-1 (IL-1) and tumor necrosis factor alpha (TNFα) in rheumatoid synovium, degrades several extracellular matrix components of cartilage and plays central roles in rheumatoid joint destruction . Therefore, monitoring serum CXCL7 and MMP-3 levels is useful for predicting the disease activity in rheumatoid arthritis. In this work, the construction and analytical performance of a dual electrochemical platform for the simultaneous determination of CXCL7 and MMP-3 is described. After the optimization of experimental variables involved in the preparation and implementation of the biosensor, the analytical usefulness of the developed configuration was demonstrated by its application to the determination of these biomarkers in serum samples from healthy individuals and patients with rheumatoid arthritis. To carry out the simultaneous determination of CXCL7 and MMP3 in human serum, just a fifty-fold sample dilution in PBS of pH 7.4 was required. In addition, the results obtained using the dual immunosensor were compared with those provided by the respective ELISA immunoassays, yielding no significant differences between the two methods. It is important to highlight that reagents consumption, four times smaller using the dual immunosensor than that required in the ELISA protocol, and an assay time of 2 h 50 min versus almost 5 h, counted in both cases after incubation of the capture antibody, are advantageous features of the dual immunosensor [5].
Different parameters affecting the preparation of the electrochemical biosensor were optimized an... more Different parameters affecting the preparation of the electrochemical biosensor were optimized and the obtained results are shown in figure 3. Fig. 3 Effect of the amount of nanohybrid (a), incubated antibody (b), time of immobilization (c) and coating with 1% BSA (d) on the normalized amperometric signal of the electrode toward 10 3 CFU/ mL Brett. Eapp = −200 mV, 100% relative current intensity = 460 nA Other parameters affecting the measurement of the yeast were optimized as shown figure 4. Fig. 4 Influence o the time (a), and temperature (b) of incubation of the immunosensor with 10 3 CFU/ mL Brett. Eapp = −200 mV, 100% relative current intensity = 460 nA The analytical performance of nanostructures immunosensor was evaluated under these optimal working conditions. This electrode allowed the amperometric detection of B. bruxellensis in buffered solutions and red wine samples in the range of 10-10 6 CFU/mL and 10 2-10 6 CFU/mL, with detection limits of 8 CFU/mL and 56 CFU/mL, resp...
Multiplexed Determination of Fertility‐related Hormones in Saliva Using Amperometric Immunosensing
Electroanalysis, 2021
Special Collection on Bioelectrochemistry
ChemElectroChem, 2019
Biomolecules, 2019
Herein, and in contrast to current production of anti-Zika virus antibodies, we propose a semi-co... more Herein, and in contrast to current production of anti-Zika virus antibodies, we propose a semi-combinatorial virtual strategy to select short peptides as biomimetic antibodies/binding agents for the detection of intact Zika virus (ZIKV) particles. The virtual approach was based on generating different docking cycles of tetra, penta, hexa, and heptapeptide libraries by maximizing the discrimination between the amino acid motif in the ZIKV and dengue virus (DENV) envelope protein glycosylation site. Eight peptides, two for each length (tetra, penta, hexa, and heptapeptide) were then synthesized and tested vs. intact ZIKV particles by using a direct enzyme linked immunosorbent assay (ELISA). As a reference, we employed a well-established anti-ZIKV antibody, the antibody 4G2. Three peptide-based assays had good detection limits with dynamic range starting from 105 copies/mL of intact ZIKV particles; this was one order magnitude lower than the other peptides or antibodies. These three pe...
Sensors, 2017
Rapid and reliable diagnosis of infectious diseases caused by pathogens, and timely initiation of... more Rapid and reliable diagnosis of infectious diseases caused by pathogens, and timely initiation of appropriate treatment are critical determinants to promote optimal clinical outcomes and general public health. Conventional in vitro diagnostics for infectious diseases are time-consuming and require centralized laboratories, experienced personnel and bulky equipment. Recent advances in electrochemical affinity biosensors have demonstrated to surpass conventional standards in regards to time, simplicity, accuracy and cost in this field. The tremendous potential offered by electrochemical affinity biosensors to detect on-site infectious pathogens at clinically relevant levels in scarcely treated body fluids is clearly stated in this review. The development and application of selected examples using different specific receptors, assay formats and electrochemical approaches focusing on the determination of specific circulating biomarkers of different molecular (genetic, regulatory and functional) levels associated with bacterial and viral pathogens are critically discussed. Existing challenges still to be addressed and future directions in this rapidly advancing and highly interesting field are also briefly pointed out.
ACS Omega, 2018
This paper describes a disposable amperometric biosensor for simple and sensitive determination o... more This paper describes a disposable amperometric biosensor for simple and sensitive determination of miRNA-21. The bioplatform consists of gold nanoparticles-nanostructured electrode surfaces on which a direct hybridization assay involving the immobilization of a specific thiolated DNA capture probe and recognition of the formed DNA-miRNA-21 heteroduplex by a specific antibody is implemented. The antibody is further recognized through its Fc region by a commercial bacterial protein containing 40 units of horseradish peroxidase (HRP) (ProtA-polyHRP40). The amperometric detection of the hybridization process using the H 2 O 2 /hydroquinone system allows quantification of the target miRNA in the 0.096-25 pM linear range with a detection limit of 29 fM (0.29 amol in 10 μL of sample). The bioplatform offers excellent selectivity against noncomplementary sequences and very acceptable against sequences with an unpaired base (only 30% of the response obtained for the target miRNA). In addition, the bioplatform was shown to be useful for the determination of the endogenous content of the target oncomiR directly in blood serum from breast cancer patients and in breast cancer cells using only 10 ng of total extracted RNA.
International Journal of Molecular Sciences, 2019
(Bio)fouling processes arising from nonspecific adsorption of biological materials (mainly protei... more (Bio)fouling processes arising from nonspecific adsorption of biological materials (mainly proteins but also cells and oligonucleotides), reaction products of neurotransmitters oxidation, and precipitation/polymerization of phenolic compounds, have detrimental effects on reliable electrochemical (bio)sensing of relevant analytes and markers either directly or after prolonged incubation in rich-proteins samples or at extreme pH values. Therefore, the design of antifouling (bio)sensing interfaces capable to minimize these undesired processes is a substantial outstanding challenge in electrochemical biosensing. For this purpose, efficient antifouling strategies involving the use of carbon materials, metallic nanoparticles, catalytic redox couples, nanoporous electrodes, electrochemical activation, and (bio)materials have been proposed so far. In this article, biomaterial-based strategies involving polymers, hydrogels, peptides, and thiolated self-assembled monolayers are reviewed and critically discussed. The reported strategies have been shown to be successful to overcome (bio)fouling in a diverse range of relevant practical applications. We highlight recent examples for the reliable sensing of particularly fouling analytes and direct/continuous operation in complex biofluids or harsh environments. Opportunities, unmet challenges, and future prospects in this field are also pointed out.
Analytica chimica acta, Jan 29, 2018
A new label-free electrochemical immunosensor is constructed for the selective and sensitive dete... more A new label-free electrochemical immunosensor is constructed for the selective and sensitive determination of the clinically relevant biomarker receptor tyrosine kinase (AXL) in human serum. The disposable immunosensing platform is prepared by immobilization of the specific anti-AXL antibody onto amine functionalized graphene quantum dots (fGQDs)-modified screen-printed carbon electrodes (SPCEs). The affinity reactions were monitored by measuring the decrease in the differential pulse voltammetric (DPV) response of the redox probe Fe(CN). All the experimental variables involved in the preparation of the modified electrodes and in the immunosensor performance were optimized. The as prepared immunosensor exhibits an improved analytical performance with respect to other electrochemical immunosensors reported so far, with a wider range of linearity and a lower detection limit, 0.5 pg mL, which is more than one hundred thousand times lower than the established cut-off value for heart fai...
Sensors (Basel, Switzerland), Jan 15, 2018
This work reports an amperometric biosensor for the determination of miRNA-21, a relevant oncogen... more This work reports an amperometric biosensor for the determination of miRNA-21, a relevant oncogene. The methodology involves a competitive DNA-target miRNA hybridization assay performed on the surface of magnetic microbeads (MBs) and amperometric transduction at screen-printed carbon electrodes (SPCEs). The target miRNA competes with a synthetic fluorescein isothiocyanate (FITC)-modified miRNA with an identical sequence for hybridization with a biotinylated and complementary DNA probe (b-Cp) immobilized on the surface of streptavidin-modified MBs (b-Cp-MBs). Upon labeling, the FITC-modified miRNA attached to the MBs with horseradish peroxidase (HRP)-conjugated anti-FITC Fab fragments and magnetic capturing of the MBs onto the working electrode surface of SPCEs. The cathodic current measured at -0.20 V (versus the Ag pseudo-reference electrode) was demonstrated to be inversely proportional to the concentration of the target miRNA. This convenient biosensing method provided a linear r...
International journal of molecular sciences, Jan 9, 2017
This work describes a sensitive amperometric magneto-biosensor for single-step and rapid determin... more This work describes a sensitive amperometric magneto-biosensor for single-step and rapid determination of microRNAs (miRNAs). The developed strategy involves the use of direct hybridization of the target miRNA (miRNA-21) with a specific biotinylated DNA probe immobilized on streptavidin-modified magnetic beads (MBs), and labeling of the resulting heteroduplexes with a specific DNA-RNA antibody and the bacterial protein A (ProtA) conjugated with an horseradish peroxidase (HRP) homopolymer (Poly-HRP40) as an enzymatic label for signal amplification. Amperometric detection is performed upon magnetic capture of the modified MBs onto the working electrode surface of disposable screen-printed carbon electrodes (SPCEs) using the H₂O₂/hydroquinone (HQ) system. The magnitude of the cathodic signal obtained at -0.20 V (vs. the Ag pseudo-reference electrode) demonstrated linear dependence with the concentration of the synthetic target miRNA over the 1.0 to 100 pM range. The method provided a d...
C, 2017
Nanotechnology is becoming increasingly important in the field of (bio)sensors. The performance a... more Nanotechnology is becoming increasingly important in the field of (bio)sensors. The performance and sensitivity of electrochemical biosensors can be greatly improved by the integration of nanomaterials into their construction. In this sense, carbon nanomaterials have been widely used for preparation of biosensors due to their ability to enhance electron-transfer kinetics, high surface-to-volume ratios, and biocompatibility. Fullerenes are a very promising family of carbon nanomaterials and have attracted great interest in recent years in the design of novel biosensing systems due to fullerenes' exceptional properties. These include multiple redox states, stability in many redox forms, easy functionalization and signal mediation. This paper outlines the state-of-the-art and future directions in the use and functionalization of fullerene-C 60 and its derivatives, both as electrode modifiers and advanced labels in electrochemical catalytic and affinity biosensors through selected applications.
Beverages, 2017
In this work, a new automated bioanalyzer based on the use of enzymatic biosensors as amperometri... more In this work, a new automated bioanalyzer based on the use of enzymatic biosensors as amperometric detectors is reported. This automatic bioanalyzer is configurable both as continuous flow and flow injection analysis systems and enables both on-line and off-line monitoring of ethanol in low-alcohol beer to be performed. The attractive analytical and operational characteristics demonstrated by the automated bioanalyzer make it a promising, simple, rapid, and reliable tool for quality control of this beverage in the beer industry, either during the manufacturing process or in the final product. Moreover its applicability to the analysis of the ethanol content in different non-alcoholic beers working at different modes was successfully demonstrated.
Chemosensors, 2017
Safety and quality are key issues of today's food industry. Since the food chain is becoming more... more Safety and quality are key issues of today's food industry. Since the food chain is becoming more and more complex, powerful analytical methods are required to verify the performance of food safety and quality systems. Indeed, such methods require high sensitivity, selectivity, ability for rapid implementation and capability of automatic screening. Electroanalytical chemistry has, for decades, played a relevant role in food safety and quality assessment, taking more and more significance over time in the solution of analytical problems. At present, the implementation of electrochemical methods in the food is evident. This is in a large part due to the relevant results obtained by combining the attractive advantages of electrochemical transduction strategies (in terms of relatively simple hardware, versatility, interface with automatic logging and feasibility of application outside the laboratory environment) with those from biosensors technology. Important examples of enzyme electrochemical biosensors are those dedicated to the determination of glucose, alcohol or cholesterol are important examples. In addition, other types of different electrochemical biosensing approaches have emerged strongly in the last years. Among these, the strategies involving affinity interactions have been shown to possess a large number of applications. Therefore, electrochemical immunosensors and DNA-based biosensors have been widely used to determine major and minor components in foodstuffs, providing sufficient data to evaluate food freshness, the quality of raw materials, or the origin of samples, as well as to determine a variety of compounds at trace levels related to food safety such as micotoxins, allergens, drugs residues or pathogen microorganisms. This review discusses some critical examples of the latest advances in this area, pointing out relevant methodologies related to the measurement techniques, including the use of nanostructured electrodes and strategies for signal amplification.
C, 2017
Growing demand for developing ultrasensitive electrochemical bioassays has led to the design of n... more Growing demand for developing ultrasensitive electrochemical bioassays has led to the design of numerous signal amplification strategies. In this context, carbon-based nanomaterials have been demonstrated to be excellent tags for greatly amplifying the transduction of recognition events and simplifying the protocols used in electrochemical biosensing. This relevant role is due to the carbon-nanomaterials' large surface area, excellent biological compatibility and ease functionalization and, in some cases, intrinsic electrochemistry. These carbon-based nanomaterials involve well-known carbon nanotubes (CNTs) and graphene as well as the more recent use of other carbon nanoforms. This paper briefly discusses the advantages of using carbon nanostructures and their hybrid nanocomposites for amplification through tagging in electrochemical biosensing platforms and provides an updated overview of some selected examples making use of labels involving carbon nanomaterials, acting both as carriers for signal elements and as electrochemical tracers, applied to the electrochemical biosensing of relevant (bio)markers.
Sensors, 2016
Ultrasensitive biosensing is currently a growing demand that has led to the development of numero... more Ultrasensitive biosensing is currently a growing demand that has led to the development of numerous strategies for signal amplification. In this context, the unique properties of magnetic particles; both of nano-and micro-size dimensions; have proved to be promising materials to be coupled with disposable electrodes for the design of cost-effective electrochemical affinity biosensing platforms. This review addresses, through discussion of selected examples, the way that nano-and micro-magnetic particles (MNPs and MMPs; respectively) have contributed significantly to the development of electrochemical affinity biosensors, including immuno-, DNA, aptamer and other affinity modes. Different aspects such as type of magnetic particles, assay formats, detection techniques, sensitivity, applicability and other relevant characteristics are discussed. Research opportunities and future development trends in this field are also considered.
Chemosensors, 2016
In this work, a novel magnetic beads (MBs)-based immunosensing approach for the rapid and simulta... more In this work, a novel magnetic beads (MBs)-based immunosensing approach for the rapid and simultaneous determination of the main peanut allergenic proteins (Ara h 1 and Ara h 2) is reported. It involves the use of sandwich-type immunoassays using selective capture and detector antibodies and carboxylic acid-modified magnetic beads (HOOC-MBs). Amperometric detection at´0.20 V was performed using dual screen-printed carbon electrodes (SPdCEs) and the H 2 O 2 /hydroquinone (HQ) system. This methodology exhibits high sensitivity and selectivity for the target proteins providing detection limits of 18.0 and 0.07 ng/mL for Ara h 1 and Ara h 2, respectively, with an assay time of only 2 h. The usefulness of the approach was evaluated by detecting the endogenous content of both allergenic proteins in different food extracts as well as trace amounts of peanut allergen (0.0001% or 1.0 mg/kg) in wheat flour spiked samples. The developed platform provides better Low detection limits (LODs) in shorter assay times than those claimed for the allergen specific commercial ELISA kits using the same immunoreagents and quantitative information on individual food allergen levels. Moreover, the flexibility of the methodology makes it readily translate to the detection of other food-allergens.
Electroanalysis : Faster Processing and Greater Service
Electroanalysis, 2016
Secuencia de nucleótido y proteína β-galactosidasa de Streptococcus mitis, procedimiento de obten... more Secuencia de nucleótido y proteína β-galactosidasa de Streptococcus mitis, procedimiento de obtención y sus aplicaciones. 57 Resumen: Secuencia de nucleótido y proteína β-galactosidasa de Streptococcus mitis, procedimiento de obtención y sus aplicaciones.