Terahertz Pumping...

Source: Technology Review

TECHNOLOGY REVIEW: One of the more significant practical challenges currently occupying molecular biologists is to find better ways of identifying short strands of DNA. Called oligonucleotides, these strands of nucleotides are hugely useful in processes such as genetic testing, forensics and DNA amplification.

But identifying the strands is a somewhat laboured business. Almost every detection method relies on fluorescent dyes and markers that can be picked up by optical sensors providing a useful but indirect indication of the molecules that are present.

But molecular biologists would like a better system that measures the characteristics of the molecules involved and so provides direct evidence of the sequence of nucleotides. Indeed, various research teams are working on such systems, some with significant success.

Today, Andrey Chernev at St Petersburg Academic University in Russia and a few pals say they have invented an entirely new way of identifying oligonucleotides using terahertz radiation. “Our results demonstrate a new method for label-free, real-time oligonucleotide characterisation,” they say.

An oligonucleotide is a short single-stranded DNA or RNA molecule usually consisting of fewer than a hundred or so bases. The sequence of these bases determines the type of oligonucleotide. So the ideal detection mechanism would reveal this sequence.

Abstract

Our results demonstrate a new method for label-free, real-time oligonucleotide characterisation by their self-resonant modes, which are unique to their conformation and sequence. We anticipate that our assay will be used as a starting point for a more detailed investigation of the aforementioned mechanism, which can be used as a basis for oligonucleotide detection and analysis. Furthermore, this technique can be applied to improve existing modern genetics technologies.

Physics arXiv: DNA Detection By THz Pumping
Andrey L. Chernev, Nicolay T. Bagraev, Leonid E. Klyachkin, Anton K. Emelyanov, Michael V. Dubina