Electrochemical detection of leukemia oncogenes using enzyme-loaded carbon nanotube labels.
Analyst
; 139(17): 4223-30, 2014 Sep 07.
Article
em En
| MEDLINE
| ID: mdl-24961450
ABSTRACT
We describe an ultrasensitive electrochemical nucleic acid assay amplified by carbon nanotubes (CNTs)-based labels for the detection of human acute lymphocytic leukemia (ALL)-related p185 BCR-ABL fusion transcript. The carboxylated CNTs were functionalized with horseradish peroxidase (HRP) molecules and target-specific detection probes (DP) via diimide-activated amidation and used to label and amplify the target hybridization signal. The activity of captured HRP was monitored by square-wave voltammetry measuring the electroactive enzymatic product in the presence of 2-aminophenol and hydrogen peroxide substrate solution. The signal-amplified assay achieved a detection limit of 83 fM (5 × 10(-18) mol in 60 µL) targets oligonucleotides and has a 4-order-wide dynamic range of target concentration. The resulting assay allowed robust discrimination between the perfect match and a three-base mismatch sequence. When exposed to the full-length (491 bp) DNA oncogene, the approach demonstrated a detection limit of 1 × 10(-16) mol in 60 µL, corresponding to approximately 33 pg of the target gene. The high sensitivity and specificity of the assay enabled a PCR-free detection of target transcripts in as little as 65 ng of mRNA extracted from positive ALL cell lines SUP-B15 in comparison to those obtained from negative cell line HL-60. The approach enables a simple, low-cost and ultrasensitive electrochemical nucleic acid detection in portable devices, point-of-care and early disease diagnostic applications.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Proteínas de Fusão bcr-abl
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Nanotubos de Carbono
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Leucemia-Linfoma Linfoblástico de Células Precursoras
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Técnicas Eletroquímicas
Tipo de estudo:
Diagnostic_studies
Limite:
Humans
Idioma:
En
Ano de publicação:
2014
Tipo de documento:
Article