Abstract
A conceptually new technique for fast DNA detection has been developed. Here, we report a fast and sensitive online fluorescence resonance energy transfer (FRET) detection technique for label-free target DNA. This method is based on changes in the FRET signal resulting from the sequence-specific hybridization between two fluorescently labelled nucleic acid probes and target DNA in a PDMS microfluidic channel. Confocal laser-induced microscopy has been used for the detection of fluorescence signal changes. In the present study, DNA hybridizations could be detected without PCR amplification because the sensitivity of confocal laser-induced fluorescence detection is very high. Two probe DNA oligomers (5′-CTGAT TAGAG AGAGAA-TAMRA-3′ and 5′-TET-ATGTC TGAGC TGCAGG-3′) and target DNA (3′-GACTA ATCTC TCTCT TACAG GCACT ACAGA CTCGA CGTCC-5′) were introduced into the channel by a microsyringe pump, and they were efficiently mixed by passing through the alligator teeth-shaped PDMS microfluidic channel. Here, the nucleic acid probes were terminally labelled with the fluorescent dyes, tetrafluororescein (TET) and tetramethyl-6-carboxyrhodamine (TAMRA), respectively. According to our confocal fluorescence measurements, the limit of detection of the target DNA is estimated to be 1.0 × 10-6 to 1.0 × 10-7 M. Our result demonstrates that this analytical technique is a promising diagnostic tool that can be applied to the real-time analysis of DNA targets in the solution phase.
Original language | English |
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Pages (from-to) | 1878-1882 |
Number of pages | 5 |
Journal | Biosensors and Bioelectronics |
Volume | 23 |
Issue number | 12 |
DOIs | |
Publication status | Published - 2008 Jul 15 |
Keywords
- Confocal laser-scanning microscopy
- DNA hybridization
- FRET
- Microfluidic sensor
- Real-time analysis
ASJC Scopus subject areas
- Biotechnology
- Biophysics
- Biomedical Engineering
- Electrochemistry