Researchers at Tokyo Institute of Technology and the University of Tokyo have provided a proof-of-concept demonstration of the world’s first “single-molecule level separation and correction” of biomolecules.
Separation and separation-based analysis of molecules are fundamentally important techniques in chemistry, biotechnology, etc. With these techniques, though, issues concerning accuracy, sensitivity and resolution regularly arise.
For example, a separation accuracy of 99% may be improved to 99.9% or 99.99%. An accuracy of 100% is not possible, in what seems an everlasting problem. This situation exists because conventional separation techniques intrinsically involve stochastic processes (mutual interaction between the separation column and analyte). Is there any way to realize 100% accuracy?
Single-molecule system
One of the possible answers is to use a single-molecule system. Theoretically, then, it can be surmised that ultimate accuracy, resolution and sensitivity should be realized using single-molecule technology that detects and manipulates only a single molecule one by one and thus does not depend on stochastic processes any more.
To prove the concept, the team has proposed and experimentally demonstrated a “single-molecule sorter” that identifies, separates and corrects individual single-molecules one by one, using DNA as a sample molecule.
Nanofluidic network
The single-molecule sorter was created using a nanofluidic network consisting of a single inlet channel that branches off into multiple outlet channels. It includes two major functional elements: a single-molecule identification element and a flow path switching element to accurately separate single-molecules.
The researchers hope to expand the application of single-molecule sorting to comprehensive sorting of all proteins from a single cell in the future. They also believe that other types of single-molecule-based processes will emerge and find use in a wide variety of applications.
Full details can be found in the journal Nanotechnology.
About the author
Takatoki Yamamoto is an associate professor at the Department of Mechanical and Control Engineering, Tokyo Institute of Technology, Tokyo, Japan. He is currently exploring nanofluidic systems for single-molecule sensing and manipulation, and application of these systems for life sciences, together with the development of nano-fabrication technology. Teruo Fujii is a professor at the Center for International Research on MicroMechatronics (CIRMM), Institute of Industrial Science, University of Tokyo. His research interests include microfluidics and its applications.
Source: http://nanotechweb.org/cws/m/1873/284783/article/lab/43923