DNA-functionalized gold nanoparticle-based fluorescence polarization for the sensitive detection of silver ions.
Colloids Surf B Biointerfaces
; 167: 150-155, 2018 Jul 01.
Article
em En
| MEDLINE
| ID: mdl-29642046
ABSTRACT
Despite their practical applications, Ag+ ions are environmental pollutants and affect human health. So the effective detection methods of Ag+ ions are imperative. Herein, we developed a simple, sensitive, selective, and cost-effective fluorescence polarization sensor for Ag+ detection in aqueous solution using thiol-DNA-functionalized gold nanoparticles (AuNPs). In this sensing strategy, Ag+ ions can specifically interact with a cytosine-cytosine (CC) mismatch in DNA duplexes and form stable metal-mediated cytosine-Ag+-cytosine (C-Ag+-C) base pairs. The formation of the C-Ag+-C complex results in evident changes in the molecular volume and fluorescence polarization signal. To achieve our aims, we prepared two complementary DNA strands containing C-base mismatches (probe A 5'-SH-A10-TACCACTCCTCAC-3' and probe B 5'-TCCTCACCAGTCCTA-FAM-3'). The stable hybridization between probe A and probe B occurs with the formation of the C-Ag+-C complex in the presence of Ag+ ions, leading to obvious fluorescence quenching in comparison to the system without AuNP enhancement. The assay can be used to identify nanomolar levels of Ag+ within 6â¯min at room temperature, and has extremely high specificity for Ag+, even in the presence of higher concentrations of interfering metal ions. Furthermore, the sensor was successfully applied to the detection of Ag+ ions in environmental water samples and showed excellent selectivity and high sensitivity, implying its promising application in the future.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Prata
/
Nanopartículas Metálicas
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Polarização de Fluorescência
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Ouro
Tipo de estudo:
Diagnostic_studies
/
Prognostic_studies
Idioma:
En
Revista:
Colloids Surf B Biointerfaces
Assunto da revista:
QUIMICA
Ano de publicação:
2018
Tipo de documento:
Article