Researchers proposed a nanosized, light-driven motor that is powerful enough to carry a certain load and possible act as a drug delivery system, according to the study published in the Journal of Chemical Physics. 

“The unprecedented characteristics of dipole photomotors based on semiconductor nanoclusters offer the prospect of more than just addressing a certain scarcity of the translational photomotors family,” lead researcher Leonid Trakhtenberg of the Moscow Institute of Physics and Technology said in prepared remarks. “These devices could actually be applied wherever rapid nanoparticle transport is required. In chemistry and physics, they could help develop new analytical and synthetic instruments, while in biology and medicine they could be used to deliver drugs to diseased tissues, improve gene therapy strategies, and so on.”

Directed nanomotors exist in nature – living organisms make use of molecular motors that can concert random motion into directed translational motion, reciprocation or rotation.

“Understanding the underlying mechanisms of the operation of naturally occurring molecular motors enables us not only to replicate them but also to design new highly efficient multi-functional artificial devices that could eventually be applied in nanorobotics,” co-author Viktor Rozenbaum, of the Chuiko Institute of Surface Chemistry of the National Academy of Sciences of Ukraine, added. “For the last several decades, researchers and engineers in various fields have been working together and making some real progress towards the development of controllable nanomachines. The results of their work were recognized as a highly relevant achievement and a significant advance in science and technology, when the 2016 Nobel Prize in Chemistry was awarded ‘for the design and synthesis of molecular machines.”

The proposed motor is activated by a laser pulse, exciting the electrons in a semiconductor nanocluster. Subjecting the nanocylinder to periodic resonant laser pulses causes the nanocylinder’s potential energy to vary with time, which in turn enables directed motion.

“Owing to the fact that the parameters of the device have been optimized, our proposed model photomotor based on a semiconductor nanocylinder moves at a record speed of 1 mm/s, which is approximately three orders of magnitude faster than similar models based on organic molecules or motor proteins in living organisms,” the authors said.