Consulta: subjectFacets:"Biosensor"
Registros recuperados: 10
Data/hora: 01/06/2024 02:29:53

Construction and application of a built-in dual luciferase reporter for microRNA functional analysis
Provedor de dados: 69
Autores: 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

Surface Plasmon Resonance sensors for oceanography
Provedor de dados: 5
Autores: Colas, Florent.
Tipo: Text
Palavras-chave: Absolute salinity; Biosensor; Molecular sensor; Refractive index; Surface functionalization; Surface plasmon resonance.
Ano: 2018
URL: https://archimer.ifremer.fr/doc/00630/74235/73866.pdf

Organometallic nanoprobe to enhance optical response on the polycyclic aromatic hydrocarbon benzo[a]pyrene immunoassay using SERS technology
Provedor de dados: 5
Autores: 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

Thiol- and Biotin-Labeled Probes for Oligonucleotide Quartz Crystal Microbalance Biosensors of Microalga Alexandrium Minutum
Provedor de dados: 5
Autores: 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

Strategy to design DNA-biosensors: Single-stranded probe grafting versus target-probe duplex grafting
Provedor de dados: 5
Autores: 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

Surface plasmon resonance in chalcogenide glass-based optical system
Provedor de dados: 5
Autores: 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

In situ QCM DNA-biosensor probe modification
Provedor de dados: 5
Autores: 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

Laser biosensor use for the microbial metabolic activity assessment of kefir vinegar
Provedor de dados: 86
Autores: 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

Enzyme-based Colorimetric and Potentiometric Biosensor for Detecting Pb (II) Ions in Milk
Provedor de dados: 52
Autores: 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

A Biosensor Using Poly(4-Aminophenol)/acetylcholinesterase modified graphite electrode for the detection of dichlorvos
Provedor de dados: 52
Autores: 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