Improved electrochemical detection of a transthyretin synthetic peptide in the nanomolar range with a two-electrode system integrated in a glass/PDMS microchip.
Lab Chip
; 14(15): 2800-5, 2014 Aug 07.
Article
em En
| MEDLINE
| ID: mdl-24902035
ABSTRACT
An alternative to a three-electrode set-up for electrochemical detection and analysis in microfluidic chips is described here. The design of the electrochemical sensor consists of the surface of the glass substrate covered with a PDMS block which bears the microfluidic channels. A band microelectrode which acts as a working electrode surrounded by a large counter electrode is obtained at the micrometric level to propose a simple and efficient sensing area for on-a-chip analysis. The counter-electrode with a surface area about 22-fold greater than the working-microelectrode can also be considered as a pseudo reference since its current density is low and thus limits the potential variations around the rest potential. To this purpose, the [Fe(III)(CN)6]³â»/[Fe(II)(CN)6]4â» redox couple was used in order to set a reference potential at 0 V since both electrodes were platinum. The electrochemical microchip performance was characterized using differential pulse voltammetric (DPV) detection and quantification of the optically multi-labelled transthyretin synthetic peptide mimicking a tryptic fragment of interest for the diagnosis of familial transthyretin amyloidosis (ATTR). The limit of detection of the peptide by the working microelectrode was 25 nM, a value 100-fold lower than the one reported with conventional capillary electrophoresis coupled with laser-induced fluorescence under the same analytical conditions.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Fragmentos de Peptídeos
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Pré-Albumina
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Técnicas Analíticas Microfluídicas
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Técnicas Eletroquímicas
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Amiloide
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Microquímica
Tipo de estudo:
Diagnostic_studies
Limite:
Humans
Idioma:
En
Revista:
Lab Chip
Assunto da revista:
BIOTECNOLOGIA
/
QUIMICA
Ano de publicação:
2014
Tipo de documento:
Article
País de afiliação:
França