Nanoengineers have demonstrated for the first time how “micromotors” that measure half the width of a human hair can be used to transport antibiotics through the body.
Nanoengineers at the University of California San Diego tested the micromotors in mice with Helicobacter pylori infections, which can also be found in about two-thirds of the world’s population and while many people will never notice any signs of its presence it can cause peptic ulcers and stomach cancer.
The mice received the micromotors – packed with a clinical dose of the antibiotic clarithromycin – orally once a day for five consecutive days.
Afterwards, nanoengineers evaluated the bacterial count in each mouse stomach and found that treatment with the micromotors was slightly more effective than when the same dose of antibiotic was given in combination with proton pump inhibitors, which also suppress gastric acid production.
Micromotors administered to the mice swam rapidly throughout the stomach while neutralising gastric acid, which can be destructive to orally administered drugs such as antibiotics and protein-based pharmaceuticals.
Because gastric acid is so destructive to traditional antibiotics drugs used to treat bacterial infections, ulcers and other diseases in the stomach are normally taken with additional substances, called proton pump inhibitors.
But when taken over longer periods or in high doses, proton pump inhibitors can cause adverse side effects including headaches, diarrhea and fatigue. In more serious cases, they can cause anxiety or depression.
The micromotors, however, have a built-in mechanism that neutralises gastric acid and effectively deliver their drug payloads in the stomach without requiring the use of proton pump inhibitors.
“It’s a one-step treatment with these micromotors, combining acid neutralisation with therapeutic action,” said Berta Esteban-Fernández de Ávila, a postdoctoral scholar in Wang’s research group at UC San Diego and a co-first author of the paper.
The nanoengineers say that while the present results are promising, this work is still at an early stage.
To test their work, the team is planning future studies to into the therapeutic performance of the micromotors in animals and humans, and will compare it with other standard therapies used to combat stomach diseases.
UC San Diego nanoengineers also plan to test different drug combinations with the micromotors to treat multiple diseases in the stomach or in different sections of the gastrointestinal tract.
Overall, the researchers say that this work opens the door to the use of synthetic motors as active delivery platforms in the treatment of diseases.
Image and video courtesy of the Laboratory for Nanobioelectronics at UC San Diego.