‘Drug delivery would certainly be an intriguing application,’ prof tells us
Tiny so-called microswimmers coated with gold can be moved around in a liquid using a laser system controlled by a machine-learning system – and scientists hope the technique will be used in some way in the future to transport drugs inside humans. Some experts believe nanomedicine, an area of research involving tiny devices capable of performing rudimentary tasks including sensing and swimming, holds much promise for things like drug delivery and surgery. One of the biggest hurdles, however, is controlling these robots once they’re in a petri dish or the human body. It’s difficult to control such small gizmos in liquid since they’re pushed in random directions by the jostling of other particles, an effect known as Brownian motion. They often have to be manually controlled in the lab using magnets or pulses of electricity. Now a team of researchers led by Leipzig University in Germany, however, believe the whole process can be automated using lasers. In an experiment described in a paper published in Science Robotics, a microswimmer some 2.18 micrometres across and coated with 8nm of gold was maneuvered in a tiny drop of solution. The microswimmer could be propelled in eight directions – such as up, down, left, right, and diagonally – using laser zaps. Heat from the laser is absorbed by the gold, and one side of the microswimmer becomes hotter than the other.
