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A Biosensor Using Poly(4-Aminophenol)/acetylcholinesterase modified graphite electrode for the detection of dichlorvos BABT
Melo,Edmar Isaías; Franco,Diego Leoni; Afonso,André Santiago; Rezende,Hélen Cristine; Brito-Madurro,Ana Graci; Madurro,João Marcos; Coelho,Nívia Maria Melo.
The properties of poly(4-aminophenol) modified graphite electrode as material for the immobilization of acetylcholinesterase were investigated by the Cyclic Voltammetry, Electrochemical Impedance Spectroscopy and Atomic Force Microscopy. The polymer was deposited on graphite electrode surface by the oxidation of 4-aminophenol and then acetylcholinesterase was immobilized on the surface of the electrode. The biosensor coupled in the continuous flow system was employed for the detection of dichlorvos. The detection and quantification limits were 0.8 and 2.4 μmol L-1 dichlorvos, respectively. Graphite electrodes modified with the poly(4-aminophenol) showed to be an efficient and promising material for immobilization of acetylcholinesterase enzyme. The...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Graphite; Poly(4-aminophenol); Biosensor; Dichlorvos.
Ano: 2011 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132011000600018
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Amperometric biosensor for Salmonella typhimurium detection in milk. Repositório Alice
ALEXANDRE, D. L.; MELO, A. M. A.; FURTADO, R. F.; BORGES, M. de F.; FIGUEIREDO, E. A. T.; BISWAS, A.; CHENG, H. N.; ALVES, C. R..
Tipo: Artigo em anais de congresso (ALICE) Palavras-chave: Salmonella; Biosensor; Electrochemical; Milk; Salmonela; Biossensor; Eletroquímico; Leite.
Ano: 2016 URL: http://www.alice.cnptia.embrapa.br/handle/doc/1059862
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Biosensor for determination of glucose in real samples of beverages Ciênc. Tecnol. Aliment.
Lopes,Flavio Marques; Batista,Karla de Aleluia; Batista,Gustavo Luiz Aleluia; Fernandes,Kátia Flávia.
A biosensor was developed for spectrophotometric determination of glucose concentrations in real samples of orange juice energetic drinks, and sport drinks. The biosensor consisted of glucose oxidase (GOD) and horseradish peroxidase (HRP) immobilized onto polyaniline activated with glutaraldehyde (PANIG). Immobilization parameters were optimized for GOD, and maximum immobilization yield was 16% when 5.0 mg of PANIG and 8.9 U prepared in 0.1 mol.L-1 sodium phosphate buffer (pH 7.0) reacted for 60 minutes at 4 °C with gentle stirring. The linear operational range for glucose determination using optimized operational parameters was between 0.05 and 6.0 mg.mL-1 with a very good reproducibility of response. The results obtained in the biosensor were compared...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Biosensor; Glucose; Glucose oxidase; Immobilization; Polyaniline.
Ano: 2012 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0101-20612012000100010
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Construction and application of a built-in dual luciferase reporter for microRNA functional analysis Electron. J. Biotechnol.
Bi,Yanzhen; Zheng,Xinmin; Shao,Changwei; Pan,Wen; Jiang,Li; Ouyang,Huiwu.
Background: As key gene regulators, microRNAs post-transcriptionally modulate gene expression via binding to partially complementary sequence in the 3? UTR of target mRNA. An accurate, rapid and quantitative tool for sensing and validation of miRNA targets is of crucial significance to decipher the functional implications of miRNAs in cellular pathways. Results: Taking advantage of an improved restriction-free cloning method, we engineered a novel built-in dual luciferase reporter plasmid where Firefly and Renilla luciferase genes were assembled in a single plasmid named ?pFila?. This design eliminates the transfection of a separate control plasmid and thus minimizes the time and labor required for miRNA-target sensing assays. pFila consistently produces...
Tipo: Journal article Palavras-chave: Biosensor; Luciferase; Ligase-independent; MiRNA; Target.
Ano: 2011 URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582011000200011
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Efeito in vitro de poluentes inorgânicos usados na agricultura sobre a atividade da catalase da alga Pseudokirchneriella subcapitata. Repositório Alice
DUARTE, S.; AMARAL SOBRINHO, N. M. B.; JONSSON, C. M.; JOKL, L..
Resumo: O efeito de poluentes em ecossistemas pode ser verifi cado pela sua ação sobre os produtores primários, como a alga Pseudokirchneriella subcapitata (Korshikov) F. Hindák (Chlorophyceae), que tem ampla distribuição em águas dulcícolas e no solo. O efeito de oito íons metálicos empregados na agricultura (alumínio, cádmio, chumbo, magnésio, manganês, mercúrio, selênio e zinco) sobre a atividade enzimática em P. subcapitata foi estudado, usando a catalase como marcador bioquímico. Alumínio, chumbo, mercúrio e zinco foram considerados inibidores e magnésio e manganês como ativadores da ação enzimática. A atividade da catalase na presença de cádmio e selênio não foi alterada. A atividade da catalase pode ser uma ferramenta promissora como biossensor...
Tipo: Artigo em periódico indexado (ALICE) Palavras-chave: Biosensor; Íons metálicos; Atividade enzimática; Pseudokirchneriella; Alga; Poluente; Impacto ambiental; Metal pesado; Algae; Biosensors; Catalase; Pollutants; Environmental impact.
Ano: 2014 URL: http://www.alice.cnptia.embrapa.br/handle/doc/1009712
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Enzyme-based Colorimetric and Potentiometric Biosensor for Detecting Pb (II) Ions in Milk BABT
Kaur,Hardeep; Kumar,Sachin; Verma,Neelam.
The aim of the present work was to study a simple colorimetric and potentiometric biosensor based on urease inhibition by Pb (II) ions for its estimation in milk samples. Urease immobilized on nylon membrane by hydrosol gel method was used as the biocomponent to demonstrate the metal effect on the enzyme activity using phenol red as the pH indicator. A lower limit detection of 38.6µm was achieved in the milk and the enzyme membranes were stable for more than two months at 4ºC. In potentiometric approach, response of an ion selective electrode (ISE) to changing ammonium ion concentration as a consequence of urease inhibition by Pb (II) ions was explored to achieve a detection limit of 9.66 µm. Lead specificity was attained by means of masking agents 1,10 -...
Tipo: Info:eu-repo/semantics/article Palavras-chave: Biosensor; Urease; Hydrosol- gel immobilization; Lead; Milk; Masking agent.
Ano: 2014 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132014000400613
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In situ QCM DNA-biosensor probe modification ArchiMer
Lazerges M, M; Perrot, H; Zeghib N, N; Antoine, Elisabeth; Compere, Chantal.
We report on a probe modification of a quartz crystal microbalance (QCM) DNA-biosensor that permits to reversibly change the DNA sequence detected. A QCM DNA-biosensor was designed by immobilization of a 20-base DNA-disulfide probe on the gold-covered quartz surface of a 27 MHz microbalance (9 MHz, third overtone). After immobilization on the gold covered quartz surface, this probe was modified by hybridization with a 45-base DNA that includes the complementary 20-base sequence, a 5-base spacer and a non-complementary 20-base sequence. The non-complementary sequence constitutes a new probe, different from the DNA-disulfide probe, that permits the detection of a new DNA target. As this 45 bases DNA is changeable by dehybridization, successive different DNA...
Tipo: Text Palavras-chave: QCM; DNA; Biosensor.
Ano: 2006 URL: http://archimer.ifremer.fr/doc/2006/publication-1985.pdf
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Laser biosensor use for the microbial metabolic activity assessment of kefir vinegar PAB
Magalhães-Guedes,Karina Teixeira; Viana,Roberta Oliveira; Braga Junior,Roberto Alves; Dias,Disney Ribeiro; Ferreira,Camila Duarte; Nunes,Itaciara Larroza; Schwan,Rosane Freitas.
Abstract: The objective of this work was to verify the use of a laser biosensor for the microbial metabolic activity assessment of kefir vinegar. Kefir grains were inoculated in apple must and were analyzed daily using the biospeckle technique. The initial biological activity was of 14.21 pixels per absolute value of differences (AVD). The biological activity of kefir grains decreased in the early days of fermentation and increased on the fourth day to 11.51 pixels per AVD; however, on the last day, the biological activity of kefir grains decreased to 7.12 pixels (alcoholic fermentation) and to 6.77 pixels per AVD (acetic fermentation). This new biospeckle methodology facilitates the microbiological control in fermentation processes.
Tipo: Info:eu-repo/semantics/article Palavras-chave: Biosensor; Biospeckle; Kefir grains; Vinegar.
Ano: 2018 URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-204X2018001101276
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Organometallic nanoprobe to enhance optical response on the polycyclic aromatic hydrocarbon benzo[a]pyrene immunoassay using SERS technology ArchiMer
Dribek, Mohamed; Rinnert, Emmanuel; Colas, Florent; Crassous, Marie-pierre; Thioune, Nene; David, Catalina; De La Chapelle, Marc; Compere, Chantal.
We demonstrated the use of a new organometallic nanoprobe for competitive surface-enhanced Raman scattering (SERS) immunoassay devoted to the detection of polycyclic aromatic hydrocarbons (PAH) such as benzo[a]pyrene (BaP) in seawater. The nanoprobes are gold nanoparticles (GNPs) labeled by a Raman reporter, the 5,5'-dithiobis(succinimidyl-2-nitrobenzoate) (DSNB) and functionalized with monoclonal antibodies anti-BaP. The antibodies are bound with a high specificity to the analyte while the GNPs enhanced the Raman scattering of the DSNB. This type of immunoassay involved the grafting of BaP onto a sensing surface. Thus, NH2-terminated self-assembled monolayer is formed on the surface of gold substrate using cysteamine. Amines finally reacted with...
Tipo: Text Palavras-chave: Biosensor; Surface-enhanced Raman scattering; Polycyclic aromatic hydrocarbons; Benzo[a]pyrene antibody; Organometallic nanoprobe.
Ano: 2017 URL: https://archimer.ifremer.fr/doc/00417/52844/53870.pdf
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Strategy to design DNA-biosensors: Single-stranded probe grafting versus target-probe duplex grafting ArchiMer
Vedrine, C.; Lazerges, M.; Perrot, H.; Compere, Chantal; Pernelle, C..
A strategy to design DNA-biosensors by grafting probe-target duplex onto a 27 MHz quartz crystal microbalance gold surface is presented in this work. The idea that removing the DNA target after duplex grafting yields to a well accessible probe, and therefore to efficient target recognition, is investigated. Unfortunately, hybridization efficiency measured using such a straightaway protocol is equal to 15%, which is feeble by comparison with the 31% hybridization efficiency measured for biosensors designed with single-stranded probe. Successive DNA biosensors are designed in this work, taking into account phenomena that occur specifically in an interfacial environment, like non specific adsorption or exchange reactions between adsorbed molecules. A...
Tipo: Text Palavras-chave: Alexandrium minutum; Biosensor; Double-stranded DNA; Quartz crystal microbalance.
Ano: 2012 URL: http://archimer.ifremer.fr/doc/00101/21196/19416.pdf
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Surface plasmon resonance in chalcogenide glass-based optical system ArchiMer
Le Person, Jenny; Colas, Florent; Compere, Chantal; Lehaitre, Michel; Anne, M; Boussard Pledel, C; Bureau, B; Adam, J; Deputier, S; Guilloux Viry, M.
The surface plasmon resonance phenomenon has been studied in a chalcogenide glass-based optical system. IR transmission properties of these materials combined to their high refractive indices lead to advantageous properties for sensing. In this study, numerical simulations have been carried out to investigate the potentialities of sulfide glass from the GeGaSbS system as a coupling prism material. Then, an angular modulation SPR biosensor has been set up in the Kretschmann-Raether arrangement. Experimental data are consistent with numerical calculation and the detection limit of the sensor is 3 x 10(-5) RIU. These preliminary results are promising. Further investigations have to be carried out to confirm the great potentialities of those materials for...
Tipo: Text Palavras-chave: Infrared; Biosensor; Surface plasmon resonance; Chalcogenide glass.
Ano: 2008 URL: http://archimer.ifremer.fr/doc/2008/publication-3955.pdf
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Thiol- and Biotin-Labeled Probes for Oligonucleotide Quartz Crystal Microbalance Biosensors of Microalga Alexandrium Minutum ArchiMer
Lazerges, Mathieu; Perrot, Hubert; Rabehagasoa, Niriniony; Compere, Chantal.
Two quartz crystal microbalance oligonucleotide biosensors of a toxic microalga gene sequence (Alexandrium Minutum) have been designed. Grafting on a gold surface of 20-base thiol- or biotin-labeled probe, and selective hybridization with the complementary 20-base target, have been monitored in situ with a 27 MHz quartz crystal microbalance under controlled hydrodynamic conditions. The frequency of the set up is stable to within a few hertz, corresponding to the nanogram scale, for three hour experiments. DNA recognition by the two biosensors is efficient and selective. Hybridization kinetic curves indicate that the biosensor designed with the thiol-labeled probe is more sensitive, and that the biosensor designed with the biotin-labeled probe has a shorter...
Tipo: Text Palavras-chave: Alexandrium Minutum; Avidin; Biosensor; Biotin; DNA; Quartz crystal miocrobalance; Self-assembled monolayer; Thiol.
Ano: 2012 URL: http://archimer.ifremer.fr/doc/00107/21810/19385.pdf
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