SERS assay of telomerase activity at single-cell level and colon cancer tissues via quadratic signal amplification.
Biosens Bioelectron
; 77: 673-80, 2016 Mar 15.
Article
em En
| MEDLINE
| ID: mdl-26496221
ABSTRACT
As an important biomarker and therapeutic target, telomerase has attracted extensive attention concerning its detection and monitoring. Recently, enzyme-assisted amplification approaches have provided useful platforms for the telomerase activity detection, however, further improvement in sensitivity is still hindered by the single-step signal amplification. Herein, we develop a quadratic signal amplification strategy for ultrasensitive surface-enhanced Raman scattering (SERS) detection of telomerase activity. The central idea of our design is using telomerase-induced silver nanoparticles (AgNPs) assembly and silver ions (Ag(+))-mediated cascade amplification. In our approach, each telomerase-aided DNA sequence extension could trigger the formation of a long double-stranded DNA (dsDNA), making numerous AgNPs assembling along with this long strand through specific Ag-S bond, to form a primary ampliï¬cation element. For secondary ampliï¬cation, each conjugated AgNP was dissolved into Ag(+), which can effectively induce the 4-aminobenzenethiol (4-ABT) modified gold nanoparticles (AuNPs@4-ABT) to undergo aggregation to form numerous "hot-spots". Through quadratic ampliï¬cations, a limit of detection down to single HeLa cell was achieved. More importantly, this method demonstrated good performance when applied to tissues from colon cancer patients, which exhibits great potential in the practical application of telomerase-based cancer diagnosis in early stages. To demonstrate the potential in screening the telomerase inhibitors and telomerase-targeted drugs, the proposed design is successfully employed to measure the inhibition of telomerase activity by 3'-azido-3'-deoxythymidine.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Prata
/
Análise Espectral Raman
/
Neoplasias do Colo
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Telomerase
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Ressonância de Plasmônio de Superfície
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Nanopartículas Metálicas
Tipo de estudo:
Diagnostic_studies
Limite:
Humans
Idioma:
En
Revista:
Biosens Bioelectron
Assunto da revista:
BIOTECNOLOGIA
Ano de publicação:
2016
Tipo de documento:
Article
País de afiliação:
China