The latest advancements in the field of targeted drug delivery has mostly involved various nanostructures, typically having antibodies attached to their surface, that are injected into the bloodstream to seek out their targets. While such nanoparticles have a great affinity toward whatever it is they are looking for, they lack any propulsion mechanism and only flow downstream. In a world’s first, researchers at University of California San Diego have created tiny micromotors that rely on a chemical reaction to function.
Scanning electron microscopy image (left) of the PEDOT/Zn micromotors and the corresponding energy-dispersive X-ray spectroscopy data (right) of elemental Zn in the micromotors.
The micromotors have zinc embedded within a polymer that reacts with stomach juices, releasing hydrogen bubbles in the reaction. This pushes the device in the direction they’re pointed, perhaps more like a rocket engine than a motor. Regardless, the devices can travel up to 60 μm per second. The team actually tested the delivery system by having mice swallow the micromotors, which, once inside the stomach, successfully bubbled their way to the walls of the stomach and wedged themselves into the gastric mucosa.
They also tested whether the micromotors could deliver something into the stomach wall and they used gold, an easily detectable material, as the cargo. The investigators were able to show that mice, that had the gold powder delivered via micromotors, had more than three times as much gold on their stomach lining as mice who simply swallowed the dust.
Open access article in ACS Nano: Artificial Micromotors in the Mouse’s Stomach: A Step toward in Vivo Use of Synthetic Motors…
(hat tip: Scientific American)