Abstract
Other than concentrating the target molecules at the sensor location, we demonstrate two distinct new advantages of an open-flow impedance-sensing platform for DNA hybridization on carbon nanotube (CNT)surface in the presence of a high-frequency AC electric field. The shear-enhanced DNA and ion transport rate to the CNT surface decouples the parasitic double-layer AC impedance signal from the charge-transfer signal due to DNA hybridization. The flow field at high AC frequency also amplifies the charge-transfer rate across the hybridized CNT and provides shear-enhanced discrimination between DNA from targeted species and a closely related congeneric species with three nucleotide mismatches out of 26 bases in a targeted attachment region. This allows sensitive detection of hybridization events in less than 20 min with picomolar target DNA concentrations in a labelfree CNT-based microfluidic detection platform.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 1823-1830 |
| Number of pages | 8 |
| Journal | ACS Nano |
| Volume | 3 |
| Issue number | 7 |
| DOIs | |
| State | Published - Jul 28 2009 |
| Externally published | Yes |
All Science Journal Classification (ASJC) codes
- General Materials Science
- General Engineering
- General Physics and Astronomy
Keywords
- Bioassay
- Carbon nanotube
- DNA hybridization
- Impedance
- Open flow