Three-dimensional Nanowire Structures for Ultra-Fast Separation of DNA, Protein and RNA Molecules.

Sakon Rahong,Tomoji Kawai,Gang Meng,Yoshinobu Baba,Fuwei Zhuge,Takao Yasui,Takeshi Yanagida,Kazuki Nagashima,Masaki Kanai,Yong He,Noritada Kaji

doi:10.1038/srep10584

Abstract

Separation and analysis of biomolecules represent crucial processes for biological and biomedical engineering development; however, separation resolution and speed for biomolecules analysis still require improvements. To achieve separation and analysis of biomolecules in a short time, the use of highly-ordered nanostructures fabricated by top-down or bottom-up approaches have been proposed. Here, we reported on the use of three-dimensional (3D) nanowire structures embedded in microchannels fabricated by a bottom-up approach for ultrafast separation of small biomolecules, such as DNA, protein, and RNA molecules. The 3D nanowire structures could analyze a mixture of DNA molecules (50–1000 bp) within 50 s, a mixture of protein molecules (20–340 kDa) within 5 s, and a mixture of RNA molecules (100–1000 bases) within 25 s. And, we could observe the electrophoretic mobility difference of biomolecules as a function of molecular size in the 3D nanowire structures. Since the present methodology allows users to control the pore size of sieving materials by varying the number of cycles for nanowire growth, the 3D nanowire structures have a good potential for use as alternatives for other sieving materials.

Highlights

To achieve separation and analysis of biomolecules in a short time, Volkmuth and Austin[11] proposed highly-ordered structures embedded in microchannelsfor separation by size and electrophoretic mobility differences
The nanopillar array of Kaji et al.[12] could separate lambda DNA digested by Hind III in 600 s under an applied DC electric field, but it was still difficult to separate DNA molecules smaller than 1 kbp due to the fabricated nanopillar size and spacing limited by electron beam lithography process
Since our method offered flexibility and simplicity to control the pore size of sieving material in the microchannels, the separation of DNA, protein, and RNA molecules could be achieved in several tens of seconds

Summary

Introduction

To achieve separation and analysis of biomolecules in a short time, Volkmuth and Austin[11] proposed highly-ordered structures embedded in microchannelsfor separation by size and electrophoretic mobility differences. Yasui et al.[13] demonstrated a non-denatured bi-mixture protein separation of trypsin inhibitor (20 kDa) and fibrinogen (340 kDa) based on the EOF mobility difference in a nanopillar array structure device under an applied DC electric field.

Results

Conclusion