Label-free detection of miRNA cancer markers based on terminal deoxynucleotidyl transferase-induced copper nanoclusters.
Anal Biochem
; 585: 113346, 2019 11 15.
Article
em En
| MEDLINE
| ID: mdl-31401004
ABSTRACT
The variations in microRNA (miRNA) expression levels can be useful biomarkers for the diagnosis of different cancers. In this work, a label-free and sensitive fluorescent method for detection of miRNA-21 is described based on duplex-specific nuclease (DSN) assist target recycling and terminal deoxynucleotidyl transferase (TdT) induced copper nanoclusters (CuNCs). In the absence of target, the 3'-phosphorylated probe DNA cannot be hydrolyzed by DSN and extended by TdT, and failed to synthesizing fluorescent CuNCs. However, the target miRNA-21 can caused the digestion of probe DNA with DSN, releasing primer DNA with 3'-OH. After that, the primer DNA can forms long poly T with the assistance of TdT, leading to synthesize high fluorescent CuNCs. The fluorescence change of CuNCs can be used to identify the concentration of target miRNA-21. Under optimal experimental conditions, this strategy could quantitatively detect miRNA-21 down to 18.7 pM. We have also demonstrated the practical application of our proposed method for monitoring miRNA-21 expression levels in cancer cells. Moreover, this method show good specificity for miRNA-21 detection due to the strong preference of DSN for cutting perfectly matched DNA/RNA duplex, which holds great potential for highly specific quantification of biomarkers in bioanalysis and clinical diagnosis.
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Base de dados:
MEDLINE
Assunto principal:
Biomarcadores Tumorais
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Cobre
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MicroRNAs
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Nanopartículas Metálicas
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Corantes Fluorescentes
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Neoplasias
Idioma:
En
Ano de publicação:
2019
Tipo de documento:
Article