Mycotoxins aptasensing: From molecular docking to electrochemical detection of deoxynivalenol.
Bioelectrochemistry
; 138: 107691, 2021 Apr.
Article
en En
| MEDLINE
| ID: mdl-33232846
ABSTRACT
This work proposes a voltammetric aptasensor to detect deoxynivalenol (DON) mycotoxin. The development steps of the aptasensor were partnered for the first time to a computational study to gain insights onto the molecular mechanisms involved into the interaction between a thiol-tethered DNA aptamer (80mer-SH) and DON. The exploited docking study allowed to find the binding region of the oligonucleotide sequence and to determine DON preferred orientation. A biotinylated oligonucleotide sequence (20mer-BIO) complementary to the aptamer was chosen to carry out a competitive format. Graphite screen-printed electrodes (GSPEs) were electrochemically modified with polyaniline and gold nanoparticles (AuNPs@PANI) by means of cyclic voltammetry (CV) and worked as a scaffold for the immobilization of the DNA aptamer. Solutions containing increasing concentrations of DON and a fixed amount of 20mer-BIO were dropped onto the aptasensor surface the resulting hybrids were labeled with an alkaline phosphatase (ALP) conjugate to hydrolyze 1-naphthyl phosphate (1-NPP) substrate into 1-naphthol product, detected by differential pulse voltammetry (DPV). According to its competitive format, the aptasensor response was signal-off in the range 5.0-30.0 ng·mL-1 DON. A detection limit of 3.2 ng·mL-1 was achieved within a 1-hour detection time. Preliminary experiments on maize flour samples spiked with DON yielded good recovery values.
Palabras clave
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Tricotecenos
/
Técnicas Biosensibles
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Aptámeros de Nucleótidos
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Simulación del Acoplamiento Molecular
Tipo de estudio:
Diagnostic_studies
Idioma:
En
Año:
2021
Tipo del documento:
Article