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
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 (email@example.com),
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.)