New DNA Molecular Motor Transports Nanoparticles

Walking mechanism of the DNA molecular motor

A new molecular motor created by a team of researchers from the Purdue University is made entirely of DNA. This miniature DNA motor also successfully demonstrated its motoring capabilities by transporting a nanoparticle across the length of a carbon nanotube.

Biological molecular motors available in nature are generally made of proteins and their performance is crucial to the functioning of cells. These naturally occurring molecular motors inside biological entities are fast and efficient, unlike their synthetic counterparts. Unlike synthetic molecular motors, these biological motors can’t be controlled and they won’t function outside biological environments either. In this research conducted by a team of researchers from the mechanical engineering and chemistry departments of the university have used DNA to create a synthetic molecular motor. This motor has two components; a core and a pair of arms made of an enzyme and DNA respectively.

The DNA molecular motor harnesses chemical energy from RNA molecules coated on the carbon nanotube for motion. The enzyme present in its core cleaves a part of RNA strand which causes the upper DNA arm to move forward to bind to the next RNA strand, and rest of the DNA follows. These steps are repeated, resulting in an autonomous movement of motor till it reaches the end of nanotube. In a demonstration, the motor was used to transport cadmium disulphide nanoparticle of 4nm diameter along the carbon nanotube which was several microns in length.

The DNA motor’s movement was tracked by using a combination of two fluorescent imaging systems, in visible and near infrared spectrum as the nanoparticles are fluorescent in visible light and nanotubes in near infrared. The research paper can be read on the journal Nature Nanotechnology.

Source: Purdue University