|Illustration of light-driven, single-molecule submersible--Courtesy of Rice University|
Researchers at Rice University claim to have invented the "fastest-moving molecules ever seen in solution," developing a molecular machine that propels itself using ultraviolet light. Though they are just a proof of concept for now, the tiny submersibles could potentially carry drugs in the future.
The scientists created a one-molecule, 244-atom submersible with a flagellum-like motor that can run at more than a million rotations per minute, according to a university report. This can push the molecule (and anything it's carrying) forward at about one inch per second.
And while many nanomachines use or generate toxic chemicals that wouldn't be suitable in a medical carrier, these motors are powered by ultraviolet light. The light excites bonds in the motor to rapidly change from double to single bonds, giving the motor one-quarter rotation per change.
To test their machines, the team used a confocal fluorescence microscope to watch one molecule at a time travel toward a red laser when hit from the other side with ultraviolet light. In terms of drug delivery, ultraviolet light could be used to direct the treatment with one or more of these molecules at a time, giving a precise location and timing of release. Their work was reported this month in the American Chemical Society journal Nano Letters.
"There's a path forward," researcher Victor García-López said in a statement. "This is the first step, and we've proven the concept. Now we need to explore opportunities and potential applications."