Department of Mechanical and Mechatronics Engineering, University of Waterloo, Waterloo, Ontario, N2L 3G1, Canada.
Department of Chemistry & Waterloo Institute for Nanotechnology (WIN), University of Waterloo, Waterloo, Ontario, N2L 3G1, Canada.
Small. 2018 Apr;14(15):e1800013. doi: 10.1002/smll.201800013. Epub 2018 Mar 5.
This paper presents a new method of sensing single molecules and cations by a carbon nanotube (CNT)-based differential resistive pulse sensing (RPS) technique on a nanofluidic chip. A mathematical model for multichannel RPS systems is developed to evaluate the CNT-based RPS signals. Individual cations, rhodamine B dye molecules, and ssDNAs are detected successfully with high resolution and high signal-to-noise ratio. Differentiating ssDNAs with 15 and 30 nucleotides are achieved. The experimental results also show that translocation of negatively charged ssDNAs through a CNT decreases the electrical resistance of the CNT channel, while translocation of positively charged cations and rhodamine B molecules increases the electrical resistance of the CNT. The CNT-based nanofluidic device developed in this work provides a new avenue for single-molecule/ion detection and offers a potential strategy for DNA sequencing.
本文提出了一种新的方法，通过基于碳纳米管（CNT）的纳米流体芯片差分电阻脉冲感应（RPS）技术来感测单分子和阳离子。开发了用于多通道 RPS 系统的数学模型，以评估基于 CNT 的 RPS 信号。成功地以高分辨率和高信噪比检测到单个阳离子、若丹明 B 染料分子和 ssDNA。实现了对 15 和 30 个核苷酸的 ssDNA 的区分。实验结果还表明，带负电荷的 ssDNA 通过 CNT 的迁移会降低 CNT 通道的电阻，而带正电荷的阳离子和若丹明 B 分子的迁移会增加 CNT 的电阻。本工作中开发的基于 CNT 的纳米流体器件为单分子/离子检测提供了新途径，并为 DNA 测序提供了一种潜在策略。
