Dissociation of ssDNA - Single-Walled Carbon Nanotube Hybrids by Watson-Crick Base Pairing

TL;DR

This study investigates how ssDNA unwraps from single-walled carbon nanotubes during Watson-Crick base pairing, revealing changes in electrical properties and providing insights for nano-bio sensing applications.

Contribution

It demonstrates the unwrapping mechanism of ssDNA from SWNTs during hybridization and offers atomistic insights through simulations, advancing nano-bio sensing technology.

Findings

Hybridization recovers metallic properties of SWNTs.

Gel electrophoresis verifies wrapping and unwrapping events.

Raman shifts reflect the unwrapping process.

Abstract

The unwrapping event of ssDNA from the SWNT during the Watson-Crick base paring is investigated through electrical and optical methods, and binding energy calculations. While the ssDNA-metallic SWNT hybrid shows the p-type semiconducting property, the hybridization product recovered metallic properties. The gel electrophoresis directly verifies the result of wrapping and unwrapping events which was also reflected to the Raman shifts. Our molecular dynamics simulations and binding energy calculations provide atomistic description for the pathway to this phenomenon. This nano-physical phenomenon will open up a new approach for nano-bio sensing of specific sequences with the advantages of efficient particle-based recognition, no labeling, and direct electrical detection which can be easily realized into a microfluidic chip format.