Protein-Based Nanoactuators

Protein-based nanoactuators can now be controlled rapidly and reversibly by thermoelectric signals. In a living creature, contracting or relaxing of muscle tissue is carried out by motor proteins called actomyosin. Scientists designing nano-scale devices would naturally like to emulate the efficiency and compactness of the muscle-moving molecules. A key issue is the controlled rapid activation of the protein motors through simple means.

And that's what researchers at Florida State University have done. They have set up a flow cell in which motor molecules (which can remain viable for days when refrigerated) can be thermally activated into motion in a controllable and reversible way using only input wires which provide a controlled amount of heat.

An important goal of this work, according to Goran Mihajlovic (goran@martech.fsu.edu), is to use the protein motors to power linear motion of nanowires; if the wires are themselves magnetic (such as nickel), then the motion could be monitored via a field sensor, such as a micro-Hall probe. The result would a bi-directional nano-actuator, controlled electrically but powered with biological energy. Possible future applications include a role in bioanalysis chips and gene delivery. (Mihajlovic et al., Applied Physics Letters, 9 August 2004.)