Beatriz Prieto-Simón

Autonomous University of Barcelona, Cerdanyola del Vallès, Catalonia, Spain

Are you Beatriz Prieto-Simón?

Claim your profile

Publications (22)84.29 Total impact

  • Núria Serrano, Beatriz Prieto-Simón, Xavier Cetó, Manel del Valle
    [Show abstract] [Hide abstract]
    ABSTRACT: This paper reports the development of three peptide modified sensors in which glutathione (GSH) and its fragments Cys-Gly and γ-Glu-Cys were immobilized respectively through aryl diazonium electrochemical grafting onto the surface of graphite-epoxy composite electrodes (GEC), and used for the simultaneous determination of Cd(II), Pb(II) and Zn(II). The concentration interval ranged from 0.1 to 1.5 μmol L-1 for each metal, and the technique used was differential pulse adsorptive stripping voltammetry. This study aimed to the comparison of the information provided by one single modified electrode at both fixed and multiple pH values (pH 6.8, 7.5 and 8.2) for the simultaneous determination of the three metals, with those supplied by the three-sensor array at multiple pH values. For the processing of the voltammograms, the fast Fourier transform was selected as the preprocessing tool for data compression coupled with an artificial neural network for the modeling of the obtained responses.
    Talanta 07/2014; 125:159-166. · 3.51 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: In this work, protein phosphatase inhibition assays (PPIAs) have been used to evaluate the performance of recombinant PP1 and recombinant and wild-type PP2As. The enzymes have been compared using microcystins-LR (MC-LR) as a model cyanotoxin. Whereas PP2ARec provides a limit of detection (LOD) of 3.1 μg/L, PP1Rec and PP2AWild provide LODs of 0.6 and 0.5 μg/L, respectively, lower than the guideline value proposed by the World Health Organization (1 μg/L). The inhibitory potencies of seven MC variants (-LR, -RR, -dmLR, -YR, -LY, -LW and -LF) have been evaluated, resulting on 50 % inhibition coefficient (IC50) values ranging from 1.4 to 359.3 μg/L depending on the MC variant and the PP. The PPIAs have been applied to the determination of MC equivalent contents in a natural cyanobacterial bloom and an artificially contaminated sample, with multi-MC profiles. The inhibition equivalency factors (IEFs) have been applied to the individual MC quantifications determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis, and the estimated MC-LR equivalent content has been compared to PPIA results. PPIAs have demonstrated to be applicable as MC screening tools for environmental applications and to protect human and animal health.
    Environmental Science and Pollution Research 05/2014; · 2.76 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We report a new label-free colorimetric aptasensor based on DNAzyme-aptamer conjugate for rapid and high-throughput detection of Ochratoxin A (OTA, a possible human carcinogen, group 2B) in wine. Two oligonucleotides were designed for this detection. One is N1 for biorecognition, which includes two adjacent sequences: the OTA-specific aptamer sequence and the horseradish peroxidase (HRP)-mimicking DNAzyme sequence. The other is a blocking DNA (B2), which is partially complementary to a part of the OTA aptamer and partially complementary to a part of the DNAzyme. The existence of OTA reduces the hybridization between N1 and B2. Thus, the activity of the non-hybridized DNAzyme is linearly correlated with the concentration of OTA up to 30nM with a limit of detection of 4nM (3σ). Meanwhile, a double liquid-liquid extraction (LLE) method is accordingly developed to purify OTA from wine. Compared with the existing HPLC-FD or immunoassay methods, the proposed strategy presents the most appropriate balance between accuracy and facility, resulting in a considerable improvement of real-time quality control, and thereby, preventing chronic poisoning caused by OTA contained red wine.
    Talanta 11/2013; 116:520-6. · 3.50 Impact Factor
  • Beatriz Prieto-Simón, Isao Karube, Hiroshi Saiki
    [Show abstract] [Hide abstract]
    ABSTRACT: Ochratoxin A (OTA) is a mycotoxin found in a wide range of food and feedstuffs. Intake of OTA-contaminated food causes health concern due to the harmful effects reported on humans and animals. Much effort is currently devoted to set up and optimise highly sensitive and accurate methods of OTA analysis. This work describes the comparison of fluorescence-based immunosensing strategies for the analysis of OTA. First, an indirect competitive fluoroimmunoassay was designed and optimised. The assay enabled the quantification of the toxin at the levels set by the European legislation. Then, a flow-immunoassay based on kinetic exclusion measurements was developed. It showed the theoretical lowest limit of detection enabled by the affinity of the anti-OTA antibody (IC(80)=12ngL(-1) in the assay solution). Wine and cereal samples were analysed using the optimised flow system. No significant matrix effects were observed after simple pre-treatment of wine and OTA extraction from corn-flakes samples. This simple and highly sensitive automated biosensing-system allows OTA quantification in food and beverages. It is envisaged as a powerful tool for rapid and reliable toxin screening.
    Food Chemistry 12/2012; 135(3):1323-9. · 3.26 Impact Factor
  • Mònica Campàs, Diana Garibo, Beatriz Prieto-Simón
    [Show abstract] [Hide abstract]
    ABSTRACT: This article gives an overview of the biosensors for the analysis of mycotoxins, marine toxins and cyanobacterial toxins, describing in depth the electrochemical biosensors that incorporate nanobiotechnological concepts. Firstly, it presents tailor-designed biomolecules, such as recombinant enzymes, recombinant antibody fragments and aptamers as novel biorecognition elements in biosensors. It also reviews the use of metallic nanoparticles (NPs) and carbon nanotubes (CNTs) aiming at improving the electrochemical transduction strategies. Finally, the exploitation of magnetic particles (MPs) as immobilisation carriers in flow-systems and the development of arrays are also described. The incorporation of these nanobiotechnological concepts provides with electrochemical biosensors with superior analytical performance in terms of specificity, sensitivity, stability and analysis time.
    The Analyst 03/2012; 137(5):1055-67. · 3.91 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: We report an aptasensor for biosensing of Ochratoxin A (OTA) using aptamer-DNAzyme hairpin as biorecognition element. The structure of this engineered nucleic acid includes the horseradish peroxidase (HRP)-mimicking DNAzyme and the OTA specific aptamer sequences. A blocking tail captures a part of these sequences in the stem region of the hairpin. In the presence of OTA, the hairpin is opened due to the formation of the aptamer-analyte complex. As a result, self-assembly of the active HRP-mimicking DNAzyme occurs. The activity of this DNAzyme is linearly correlated with OTA concentration up to 10 nM, showing a limit of detection of 2.5 nM.
    Biosensors & Bioelectronics 02/2012; 32(1):208-12. · 6.45 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Ochratoxin A (OTA) is one of the most important mycotoxins because of its high toxicity to both humans and animals and its occurrence in a number of basic foods and agro-products. The need to develop high-performing methods for OTA analysis able to improve the traditional ones is evident. In this work, through in vitro SELEX (Systematic Evolution of Ligands by EXponential enrichment) two aptamers, designated H8 and H12 were produced that bind with nanomolar affinity with Ochratoxin A (OTA). Two strategies were investigated by using an indirect and a direct competitive Enzyme-Linked Aptamer Assay (ELAA) and were compared to the classical competitive Enzyme-Linked Immunosorbent Assay (ELISA) for the determination of OTA in spiked red wine samples. The limit of detection attained (1 ng/mL), the midpoint value obtained (5 ng/mL) and the analysis time needed (125 min) for the real sample analysis validate the direct competitive ELAA as useful screening tool for routine use in the control of OTA level in wine.
    Food Control 05/2011; · 2.82 Impact Factor
  • Beatriz Prieto-Simón, Mònica Campàs, Jean-Louis Marty
    [Show abstract] [Hide abstract]
    ABSTRACT: The valuable properties of aptamers, such as specificity, sensitivity, stability, cost-effectiveness and design flexibility, have favoured their use as biorecognition elements in biosensor development. These synthetic affinity probes can be developed for almost any target molecule, covering a wide range of applications in fields such as clinical diagnosis and therapy, environmental monitoring and food control. The combination of aptamers with high-performance electrochemical transducers, with their inherent high sensitivities, fast response times and simple equipment, has already provided several electrochemical aptamer-based sensors. Moreover, the small size and versatility of aptamers allow efficient immobilisations in high-density monolayers, an important feature towards miniaturisation and integration of compact electrochemical devices. This review describes the state-of-the-art of electrochemical aptamer-based sensors, entering into the details of the different strategies and types of electrochemical transduction and also considering their advantages when applied to the analysis of complex matrices. KeywordsAptamer-Biosensor-Electrochemical detection-Aptabeacon-Redox label
    Bioanalytical Reviews 08/2010; 1(2):141-157.
  • [Show abstract] [Hide abstract]
    ABSTRACT: Free radicals are highly reactive molecules generated during cellular metabolism. However, their overproduction results in oxidative stress, a deleterious process that can damage cell structures, including lipids and membranes, proteins and DNA. Antioxidants respond to this problem, scavenging free radicals. This chapter critically reviews the electrochemical biosensors developed for the evaluation of the antioxidant capacity of specific compounds. Due to the ability of these devices to perform simple, fast and reliable analysis, they are promising biotools for the assessment ofantioxidant properties.
    Advances in Experimental Medicine and Biology 01/2010; 698:222-33. · 2.01 Impact Factor
  • Monica Campàs, Beatriz Prieto-Simón, Régis Rouillon
    [Show abstract] [Hide abstract]
    ABSTRACT: Secondary metabolites are chemical compounds that are not directly involved in the normal growth, development or reproduction of organisms. Due to the toxicity shown by some of these compounds, their presence can represent a threat to human health. Reliable detection systems able to control their presence are required, as a tool to ensure public health. This chapter offers an overview of different techniques developed for the detection of toxic secondary metabolites, taking ochratoxin A and microcystins as two representative examples. While ochratoxin A is a mycotoxin produced by several species of fungi, microcystins are cyanotoxins released by certain strains of cyanobacteria. Biosensor-based strategies are emphasized as powerful screening tools.
    Advances in Experimental Medicine and Biology 01/2010; 698:282-92. · 2.01 Impact Factor
  • Beatriz Prieto-Simón, Hirotaka Miyachi, Isao Karube, Hiroshi Saiki
    [Show abstract] [Hide abstract]
    ABSTRACT: Episodes of shellfish contamination with okadaic acid (OA) are a human health threat that is causing increasing concern. As a way to overcome the shortcomings involved in the reference methods of analysis set by legislations, alternative procedures are envisaged. This paper describes the development of different immunosensors for the analysis of OA, focusing on the comparison of their sensitivity, precision, ease of use and sample matrix effects. Initially, a surface plasmon resonance (SPR)-based immunosensor was developed, which enabled the quantification of the toxin in mussel samples at concentrations in the range of the 160 microg kg(-1) European regulatory limit with good percentages of recovery. Nevertheless, calibration curves with spiked mussel samples showed that matrix effects could not be neglected. Alternatively, a flow-immunosensing system based on kinetic exclusion measurements was developed achieving the theoretical lowest limit of detection enabled by the affinity of the anti-OA antibody (IC(70)=0.03 microg L(-1) in the assay solution). This highly sensitive automated system allows rapid and reliable OA quantification, with no significant matrix effects for the analysis of spiked mussel and scallop samples. Performance features such as high sensitivity and precision, low limits of detection and simplicity of the analysis protocol, shows the biosensing-systems based on kinetic exclusion measurements for toxin detection in shellfish samples as highly performing tools for rapid and continuous screening.
    Biosensors & Bioelectronics 10/2009; 25(6):1395-401. · 6.45 Impact Factor
  • Beatriz Prieto-Simón, Mònica Campàs
    [Show abstract] [Hide abstract]
    ABSTRACT: AbstractAs a result of the deleterious effects of mycotoxins on human and animal health, and the consequently increasing stringency in the determination of food contamination levels, many researchers have focused their efforts on developing new devices for the detection of these compounds. Biosensors merit special mention due to their sensitivity, accuracy, cost-effectiveness and simplicity, not only of the construction, but also of the sample pre-treatment, if necessary, and the measurement step. Furthermore, biosensor arrays offer additional advantages, such as the possibility to measure multiple samples and provide multi-mycotoxin profiles in one assay. In this case, apart from shortening the analysis time, accuracy is improved by the assessment of matrix interferences and synergistic effects among mycotoxins. Biosensors and arrays for mycotoxins are thus promising biotechnological tools for mycotoxin detection in food. Graphical Abstract
    Monatshefte fuer Chemie/Chemical Monthly 08/2009; 140(8):915-920. · 1.35 Impact Factor
  • Mònica Campàs, Beatriz Prieto-Simón, Jean-Louis Marty
    [Show abstract] [Hide abstract]
    ABSTRACT: This article gives an overview of the electrochemical biosensors that incorporate genetically modified enzymes. Firstly, the improvements on the sensitivity and selectivity of biosensors that integrate mutated enzymes are summarised. Next, new trends focused on the oriented immobilisation of mutated enzymes through specific functional groups located at their surface are reviewed. Finally, the effect of enzyme mutations on the electron transfer distance and kinetics of electrochemical biosensors is described.
    Seminars in Cell and Developmental Biology 03/2009; 20(1):3-9. · 5.97 Impact Factor
  • Beatriz Prieto-Simón, Mònica Campàs
    Stewart Postharvest Review 12/2008; 4(6):1-7.
  • Source
    A Radoi, M Targa, B Prieto-Simon, J-L Marty
    [Show abstract] [Hide abstract]
    ABSTRACT: Five different clones of antibodies developed against the aflatoxin M(1) were investigated by using the classical indirect and direct competitive Enzyme-Linked Immunosorbent Assay (ELISA) formats, and also the direct competitive ELISA based on the use of the superparamagnetic nanoparticles. The purpose of this study was to assess if not so friendly time classical ELISA procedures can be further improved, by reducing the coating, blocking and competition time. Here we showed that a complete dc-ELISA (coating, blocking and competition step) based on the use of superparamagnetic nanoparticles can be performed in basically 40 min, if coating step (20 min) should be taken into account. Moreover, the standard analytical characteristics of the proposed method fulfil the requirements for detecting AFM(1) in milk, in a wide linear working range (4-250 ng/L). The IC(50) value is 15 ng/L. The matrix effect and the recovery rate were assessed, using the European Reference Material (BD282, zero level of AFM(1)), showing an excellent percentage of recovery, close to 100%.
    Talanta 11/2008; 77(1):138-43. · 3.50 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The increasing concern about ochratoxin A (OTA) contamination of different food and feedstuffs demands high-performing detection techniques for quality assessment. Two indirect competitive enzyme-linked immunosorbent assay (ELISA) strategies were investigated for the development of OTA electrochemical immunosensors based on different OTA immobilisation procedures. Immunosensors based on avidin/biotin-OTA showed enhanced performance characteristics compared to those based on the adsorption of bovine serum albumin (BSA)-OTA conjugate. Performance of polyclonal (PAb) and monoclonal (MAb) antibodies against OTA was compared, showing at least one-order of magnitude lower IC(50) values when working with MAb. Alkaline phosphatase (ALP)- and horseradish peroxidase (HRP)-labelled secondary antibodies were evaluated. Both conjugates led to similar results when working with OTA standard solutions in buffer. However, whereas electroactive interferences present in spiked wine samples did not affect HRP-labelled immunosensors (4% slope deviation), they were likely oxidised at 0.225 V versus Ag/AgCl, the working potential for ALP-labelled immunosensors (25% slope deviation). Considering 80% of antibody binding as the limit of detection, values of 0.7 and 0.3 ng/mL for HRP- and ALP-labelled immunosensors respectively, validate these immunosensors as useful screening tools to assess OTA levels in wine.
    Biosensors & Bioelectronics 03/2008; 23(7):995-1002. · 6.45 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Oxidative stress arises from the excess of free radicals due to environmental or behavioural stressors, or simply to a malfunction of the antioxidant production. It produces damage to lipids, proteins or DNA, impeding normal cell functioning and leading to numerous human diseases, as well as to the aging process. Antioxidants respond to this problem, scavenging the free radicals. This article critically reviews the electrochemical biosensors developed for the evaluation of the antioxidant capacity of specific compounds. Three different sensing approaches are described, based on cytochrome c, superoxide dismutase and DNA. Due to the ability of these devices to perform simple, fast and reliable analysis, they are promising biotools for the assessment of antioxidant properties.
    Sensors and Actuators B Chemical 01/2008; · 3.84 Impact Factor
  • B. Prieto-Simón, T. Noguer, M. Campàs
    [Show abstract] [Hide abstract]
    ABSTRACT: Mycotoxins are secondary metabolites that moulds produce naturally. Due to their ubiquitous presence in foodstuffs and their potential risk for human health, prompt detection is important. In this review, we present and critically compare recent advances in mycotoxin analysis. Although most validated detection methods are chromatographic, alternative strategies based on biosensing principles are emerging. Biosensors and sensor arrays provide selective, sensitive and accurate measurements. The feasibility of miniaturizing them so that they are portable, their simplicity and easy data interpretation make them useful as screening biotools to ensure the correct assessment of mycotoxins in food and to reassure the consumer.
    TrAC Trends in Analytical Chemistry 07/2007; · 6.61 Impact Factor
  • Beatriz Prieto-Simón, Esteve Fàbregas, Alan Hart
    [Show abstract] [Hide abstract]
    ABSTRACT: Two strategies were investigated for the development of lactate biosensors based on sol-gel matrixes and polysulfone composite films, both containing L-lactate dehydrogenase (LDH). Firstly, reagentless disposable screen-printed electrodes (SPE's) with Meldola's Blue (MB) and the cofactor NAD(+) inside a sol-gel matrix were prepared. These showed relatively low sensitivities (260 microA/M). Secondly, mediator-modified-polysulfone-graphite composite films deposited over both cylindrical epoxy-graphite and SPE's. These electrodes showed enhanced performance characteristics: improved sensitivity (80 mA/M), detection limit (0.87 microM) and reproducibility (2%). Reagentless electrodes, incorporating NAD(+) in the polysulfone film, had a decreased sensitivity, although better than that achieved by the sol-gel electrodes. While sol-gel electrodes showed a linear range between 1.25 x 10(-4) and 2.48 x 10(-3)M, the epoxy-graphite composite electrodes based on polysulfone composite films allowed the detection of lactate at a linear range of lower concentrations from 1 x 10(-6) to 1.2 x 10(-5)M. Finally, the performance of the LDH-MB-polysulfone-composite film-based SPE's in a flow system was studied. Short response times were obtained (t<30s). Furthermore, repeatability and reproducibility values were notably improved, especially when working with electrodes covered with a polyamide layer prepared with N-(2-aminoethyl)-piperazine.
    Biosensors & Bioelectronics 06/2007; 22(11):2663-8. · 6.45 Impact Factor
  • Source
    Mònica Campàs, Beatriz Prieto-Simón, Jean-Louis Marty
    [Show abstract] [Hide abstract]
    ABSTRACT: This article describes the different types of marine toxins and their toxic effects, and reviews the bio/analytical techniques for their detection, putting special emphasis to biosensors. Important health concerns have recently appeared around shellfish (diarrheic, paralytic, amnesic, neurologic and azaspiracid) and fish (ciguatera and puffer) poisonings produced by different types of phycotoxins, making evident the urgent necessity of counting on appropriate detection technologies. With this purpose, several analysis methods (bioassays, chromatographic techniques, immunoassays and enzyme inhibition-based assays) have been developed. However, easy-to-use, fast and low-cost devices, able to deal with complicated matrices, are still required. Biosensors offer themselves as promising biotools, alternative and/or complementary to conventional analysis techniques, for fast, simple, cheap and reliable toxicity screening. Nevertheless, despite the wide range of seafood toxins and the already rooted biosensing systems, the literature on biosensors for phycotoxins is scarce. This article discusses the existing biosensor-based strategies and their advantages and limitations. Finally, the article gives a general overlook about the regulation toxin levels and monitoring programmes currently established around the world concerning seafood safety.
    Talanta 06/2007; 72(3):884-95. · 3.50 Impact Factor

Publication Stats

296 Citations
84.29 Total Impact Points


  • 2007–2014
    • Autonomous University of Barcelona
      • Department of Chemistry
      Cerdanyola del Vallès, Catalonia, Spain
  • 2012
    • IRTA Institute of Agrifood Research and Technology
      Barcino, Catalonia, Spain
  • 2011–2012
    • IBEC Institute for Bioengineering of Catalonia
      Barcino, Catalonia, Spain
  • 2009–2012
    • Tokyo University of Technology
      • • School of Bioscience and Biotechnology
      • • School of Bionics
      Edo, Tōkyō, Japan
  • 2007–2010
    • Université de Perpignan
      • IMAgES Institute of Modelling and Analysis in Geo- Environment and Health
      Perpinyà, Languedoc-Roussillon, France
  • 2006–2007
    • University of Barcelona
      • Departament de Química Física
      Barcelona, Catalonia, Spain