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Article: Correction to Rapid Identification and Quantification of Tumor Cells Using an Electrocatalytic Method Based on Gold Nanoparticles.
Alfredo de la Escosura-Muñiz, Christian Sánchez-Espinel, Belén Díaz-Freitas, Africa González-Fernández, Marisa Maltez-da Costa, Arben MerkoçiAnalytical Chemistry 03/2012; · 5.86 Impact Factor -
SourceAvailable from: Africa González-Fernández
Article: Gold nanoparticle-based electrochemical magnetoimmunosensor for rapid detection of anti-hepatitis B virus antibodies in human serum.
Alfredo de la Escosura-Muñiz, Marisa Maltez-da Costa, Christian Sánchez-Espinel, Belén Díaz-Freitas, Jonathan Fernández-Suarez, África González-Fernández, Arben Merkoçi[show abstract] [hide abstract]
ABSTRACT: A sandwich immunoassay using magnetic beads as bioreaction platforms and AuNPs as electroactive labels for the electrochemical detection of human IgG antibodies anti-Hepatitis B surface antigen (HBsAg), is here presented as an alternative to the standard methods used in hospitals for the detection of human antibodies directed against HBsAg (such as ELISA or MEIA). The electrochemical detection of AuNPs is carried out approaching their catalytic properties towards the hydrogen evolution in an acidic medium, without previous nanoparticle dissolution. The obtained results are a good promise toward the development of a fully integrated biosensing set-up. The developed technology based on this detection mode would be simple to use, low cost and integrated into a portable instrumentation that may allow its application even at doctor-office. The sample volumes required can be lower than those used in the traditional methods. This may lead to several other applications with interest for clinical control.Biosensors & bioelectronics 12/2010; 26(4):1710-4. · 5.43 Impact Factor -
SourceAvailable from: Africa González-Fernández
Article: Rapid identification and quantification of tumor cells using an electrocatalytic method based on gold nanoparticles.
Alfredo de la Escosura-Muñiz, Christian Sánchez-Espinel, Belén Díaz-Freitas, Africa González-Fernández, Marisa Maltez-da Costa, Arben Merkoçi[show abstract] [hide abstract]
ABSTRACT: There is a high demand for simple, rapid, efficient, and user-friendly alternative methods for the detection of cells in general and, in particular, for the detection of cancer cells. A biosensor able to detect cells would be an all-in-one dream device for such applications. The successful integration of nanoparticles into cell detection assays could allow for the development of this novel class of cell sensors. Indeed, their application could well have a great future in diagnostics, as well as other fields. As an example of a novel biosensor, we report here an electrocatalytic device for the specific identification of tumor cells that quantifies gold nanoparticles (AuNPs) coupled with an electrotransducing platform/sensor. Proliferation and adherence of tumor cells are achieved on the electrotransducer/detector, which consists of a mass-produced screen-printed carbon electrode (SPCE). In situ identification/quantification of tumor cells is achieved with a detection limit of 4000 cells per 700 microL of suspension. This novel and selective cell-sensing device is based on the reaction of cell surface proteins with specific antibodies conjugated with AuNPs. Final detection requires only a couple of minutes, taking advantage of the catalytic properties of AuNPs on hydrogen evolution. The proposed detection method does not require the chemical agents used in most existing assays for the detection of AuNPs. It allows for the miniaturization of the system and is much cheaper than other expensive and sophisticated methods used for tumor cell detection. We envisage that this device could operate in a simple way as an immunosensor or DNA sensor. Moreover, it could be used, even by inexperienced staff, for the detection of protein molecules or DNA strands.Analytical Chemistry 11/2009; 81(24):10268-74. · 5.86 Impact Factor -
Patent: (EN) METHOD FOR CELL IDENTIFICATION AND QUANTIFICATION WITH GOLD NANOPARTICLES THROUGH HYDROGEN ION REDUCTION (ES) MÉTODO DE IDENTIFICACIÓN Y CUANTIFICACIÓN DE CÉLULAS CON NANOPARTÍCULAS DE ORO POR REDUCCIÓN DE IONES HIDRÓGENO
MERKOÇI HYKA, Arben, ES). DE LA ESCOSURA MUÑIZ, Alfredo, ES). GONZÁLEZ FERNÁNDEZ, Africa, ES). DÍAZ FREITAS, Belén, ES). SÁNCHEZ ESPINEL, Christian, ES[show abstract] [hide abstract]
ABSTRACT: EN) The method for cell identification and quantification comprises bonding specific surface proteins of cells immobilised on the surface of the electrochemical transducer with specific antibodies conjugated with gold nanoparticles, and subsequent nanoparticle detection and quantification through hydrogen generation catalysed by said nanoparticles at an appropriate potential. It furthermore comprises the application thereof in a method of diagnosis and/or prognosis of a disease involving the expression of cell-surface proteins and the corresponding kits. (ES) El método de identificación y cuantificación de células comprende la unión de proteínas específicas de superficie de las células inmovilizadas en la superficie del transductor electroquímico con anticuerpos específicos conjugados con nanopartículas de oro, y la posterior detección y cuantificación de la nanopartícula mediante la generación de hidrógeno catalizada por dicha nanopartícula a un potencial apropiado. También comprende su aplicación en un método de diagnóstico y/o pronóstico de una enfermedad que implique la expresión de proteínas de superficie de las células y los kits correspondientes.Ref. No: PCT/ES2009/070489, Year: 01/2009 -
SourceAvailable from: Africa González-Fernández
Article: Assessing methods for blood cell cytotoxic responses to inorganic nanoparticles and nanoparticle aggregates.
Belén Díaz, Christian Sánchez-Espinel, Manuel Arruebo, José Faro, Encarnación de Miguel, Susana Magadán, Clara Yagüe, Rodrigo Fernández-Pacheco, M Ricardo Ibarra, Jesús Santamaría, Africa González-Fernández[show abstract] [hide abstract]
ABSTRACT: Inorganic nanoparticles (NPs) show great potential for medicinal therapy. However, biocompatibility studies are essential to determine if they are safe. Here, five different NPs are compared for their cytotoxicity, internalization, aggregation in medium, and reactive oxygen species (ROS) production, using tumoral and normal human blood cells. Differences depending on the cell type are analyzed, and no direct correlation between ROS production and cell toxicity is found. Results are discussed with the aim of standardizing the procedures for the evaluation of the toxicity.Small 11/2008; 4(11):2025-34. · 8.35 Impact Factor