Denaturation strategies for detection of double stranded PCR products on GMR magnetic biosensor array.
Biosens Bioelectron
; 93: 155-160, 2017 Jul 15.
Article
em En
| MEDLINE
| ID: mdl-27650710
ABSTRACT
Microarrays and other surface-based nucleic acid detection schemes rely on the hybridization of the target to surface-bound detection probes. We present the first comparison of two strategies to detect DNA using a giant magnetoresistive (GMR) biosensor platform starting from an initially double-stranded DNA target. The target strand of interest is biotinylated and detected by the GMR sensor by linking streptavidin magnetic nanoparticles (MNPs) to the sensor surface. The sensor platform has a dynamic detection range from 40pM to 40nM with highly reproducible results and is used to monitor real-time binding signals. The first strategy, using off-chip heat denaturation followed by sequential on-chip incubation of the nucleic acids and MNPs, produces a signal that stabilizes quickly but the signal magnitude is reduced due to competitive rehybridization of the target in solution. The second strategy, using magnetic capture of the double-stranded product followed by denaturing, produces a higher signal but the signal increase is limited by diffusion of the MNPs. Our results show that both strategies give highly reproducible results but that the signal obtained using magnetic capture is higher and insensitive to rehybridization.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
DNA
/
Técnicas Biossensoriais
/
Nanopartículas de Magnetita
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Fenômenos Magnéticos
Tipo de estudo:
Diagnostic_studies
Idioma:
En
Revista:
Biosens Bioelectron
Ano de publicação:
2017
Tipo de documento:
Article