Ultrasensitive photoelectrochemical aptasensor for lead ion detection based on sensitization effect of CdTe QDs on MoS2-CdS:Mn nanocomposites by the formation of G-quadruplex structure.
Talanta
; 183: 237-244, 2018 Jun 01.
Article
en En
| MEDLINE
| ID: mdl-29567170
ABSTRACT
An ultrasensitive photoelectrochemical (PEC) aptasensor for lead ion (Pb2+) detection was fabricated based on MoS2-CdSMn nanocomposites and sensitization effect of CdTe quantum dots (QDs). MoS2-CdSMn modified electrode was used as the PEC matrix for the immobilization of probe DNA (pDNA) labeled with CdTe QDs. Target DNA (tDNA) were hybridized with pDNA to made the QDs locate away from the electrode surface by the rod-like double helix. The detection of Pb2+ was based on the conformational change of the pDNA to G-quadruplex structure in the presence of Pb2+, which made the labeled QDs move close to the electrode surface, leading to the generation of sensitization effect and evident increase of the photocurrent intensity. The linear range was 50â¯fM to 100â¯nM with a detection limit of 16.7â¯fM. The recoveries of the determination of Pb2+ in real samples were in the range of 102.5-108.0%. This proposed PEC aptasensor provides a new sensing strategy for various heavy metal ions at ultralow levels.
Palabras clave
Texto completo:
1
Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Técnicas Biosensibles
/
Puntos Cuánticos
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Aptámeros de Nucleótidos
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G-Cuádruplex
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Técnicas Electroquímicas
/
Plomo
Tipo de estudio:
Diagnostic_studies
Idioma:
En
Revista:
Talanta
Año:
2018
Tipo del documento:
Article