DNA hybridization detection in a microfluidic channel using two fluorescently labelled nucleic acid probes

详细信息	查看全文 | 推荐本文 |

• 作者：Lingxin Chen ; Sangyeop Lee ; Moonkwon Lee ; Chaesung Lim ; Jaebum Choo ; Joong Yull Park ; Sanghoon Lee ; Sang-Woo Joo ; Kyeong-Hee Lee ; Young-Wook Choi
• 关键词：FRET ; Microfluidic sensor ; DNA hybridization ; Confocal laser-scanning microscopy ; Real-time analysis
• 刊名：Biosensors and Bioelectronics
• 出版年：2008
• 期刊代码：12_09565663
• 类别：ch
• 出版时间：15 July 2008
• 卷：23
• 期：12
• 页码：1878-1882
• 文件大小：527 K

摘要

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.