An electrochemical sensing platform based on ladder-shaped DNA structure and label-free aptamer for ultrasensitive detection of ampicillin.
Biosens Bioelectron
; 133: 230-235, 2019 May 15.
Article
em En
| MEDLINE
| ID: mdl-30951983
ABSTRACT
Herein, an electrochemical aptasensor is described for detection of ampicillin (Ampi). The sensing strategy is based on the application of a ladder-shaped DNA structure as a multi-layer physical block on the surface of gold electrode. Attributing to the electrostatic repulsion and physical prevention of the ladder-shaped DNA structure, ultrasensitive detection of Ampi was achieved with a detection limit as low as 1â¯pM. In the presence of Ampi, the ladder-shaped DNA structure is disassembled and detached from the electrode surface. This leads to the high access of [Fe(CN)6]3-/4- as a redox indicator to the electrode surface and a strong redox peak. The aptasensor response for Ampi detection was in the linear range from 7â¯pM to 100â¯nM with the detection limit of 1â¯pM. The presented analytical strategy showed its application in detecting Ampi in the spiked milk samples with satisfactory performance. This work can be easily expanded for different targets by alternating the corresponding aptamers.
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Texto completo:
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Base de dados:
MEDLINE
Assunto principal:
DNA
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Técnicas Biossensoriais
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Técnicas Eletroquímicas
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Ampicilina
Tipo de estudo:
Diagnostic_studies
Limite:
Animals
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Humans
Idioma:
En
Ano de publicação:
2019
Tipo de documento:
Article