Enhanced detection of quantum dots labeled protein by simultaneous bismuth electrodeposition into microfluidic channel
Medina-Sánchez, Mariana (Institut Català de Nanociència i Nanotecnologia)
Miserere, Sandrine (Institut Català de Nanociència i Nanotecnologia)
Cadevall Riera, Miquel (Institut Català de Nanociència i Nanotecnologia)
Merkoçi, Arben (Institut Català de Nanociència i Nanotecnologia)

Date:	2016
Abstract:	In this study, we propose an electrochemical immunoassay into a disposable microfluidic platform, using quantum dots (QDs) as labels and their enhanced detection using bismuth as an alternative to mercury electrodes. CdSe@ZnS QDs were used to tag human IgG as a model protein and detected through highly sensitive stripping voltammetry of the dissolved metallic component (cadmium in our case). The modification of the screen printed carbon electrodes (SPCEs) was done by a simple electrodeposition of bismuth that was previously mixed with the sample containing QDs. A magneto-immunosandwich assay was performed using a micromixer. A magnet placed at its outlet in order to capture the magnetic beads used as solid support for the immunoassay. SPCEs were integrated at the end of the channel as detector. Different parameters such as bismuth concentration, flow rate, and incubation times, were optimized. The LOD for HIgG in presence of bismuth was 3. 5 ng/mL with a RSD of 13. 2%. This LOD was about 3. 3-fold lower than the one obtained without bismuth. Furthermore, the sensitivity of the system was increased 100-fold respect to experiments carried out with classical screen-printed electrodes, both in presence of bismuth.
Grants:	European Commission 246513 Ministerio de Economía y Competitividad MAT2014-52485-P Ministerio de Economía y Competitividad SEV-2013-0295 Ministerio de Ciencia e Innovación MAT2011-25870 Agència de Gestió d'Ajuts Universitaris i de Recerca 2014/SGR-260
Rights:	Tots els drets reservats.
Language:	Anglès
Document:	Article ; recerca ; Versió acceptada per publicar
Subject:	Bismuth ; Electrochemistry ; HIgG ; Magnetic Beads ; Microfluidics ; Quantum dots
Published in:	Electrophoresis, Vol. 37, issue 3 (Feb. 2016) , p. 432-437, ISSN 1522-2683

DOI: 10.1002/elps.201500288

Postprint 26 p, 1.3 MB

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Research literature > UAB research groups literature > Research Centres and Groups (research output) > Experimental sciences > Catalan Institute of Nanoscience and Nanotechnology (ICN2)
Articles > Research articles
Articles > Published articles