The baby boomers had milk deliveries. Millennials have drone deliveries. The next generation might now have tiny robotic medicine deliveries.
For the first time, micromotors have cured a bacterial infection in a mouse’s stomach through the use of bubbles to power the movement of antibiotics. A micromotor is an autonomous vehicle that is as wide as a human hair.
A research team hailing from of the University of California San Diego used micromotors to administer medicine to mice with stomach infections for five continuous days. At the end of the five days, the team found that the micromotor approach was more effective than a regular medicinal dosing schedule.
“The movement [of a micromotor] itself improves the retention of antibiotics on the stomach lining where the bacteria are concentrated,” says Joseph Wang. Wang, along with Liangfang Zhang, led the research.
The tiny delivery method consists of a spherical magnesium core that is coated with several layers that provide protection, treatment and the power to stick to stomach walls. The mouse would swallow the treatment and then the magnesium core would react with the acid inside the stomach to create a stream of hydrogen bubbles that would push the motors around. The entire process reduces acidity levels in the stomach, and because the antibiotic layer of the micromotor is sensitive to the surrounding acidity, the sudden lowering of levels releases the bacteria fighting medicine.
Acidity levels must be reduced before any kind of antibiotics or protein-based medicines can achieve any kind of success. This layer-shedding mechanism shows that drugs normally used to treat bacterial infections like ulcers can perhaps be taken without a proton pump inhibitor. Those inhibitors are used to suppress gastric acid production and long-term use of the device can have serious side-effects on humans. Micromotor medicine delivery could signal the end of fatigue, headache and even anxiety side effects for those with bacterial infections that take traditional forms of medicine.
“There is still a long way to go, but we are on a fantastic voyage,” says Wang.
Stomach acid levels return to normal after a day and the micromotors and their layers dissolve harmlessly. The next steps would be a study in a larger animal, then potentially humans with bacterial infections.
“It’s a really nifty and impressive application. Micromotors are still new, but their impact will be big,” said Thomas Mallouk, head of the chemistry department at Pennsylvania State University.
In the future, the technology can be used to treat diseases like Parkinson’s or Alzheimer’s. Micromotors can even be used in the treatment of biological or chemical weapon attacks like those using Sarin gas—normally the machines that mix neutralizing compounds are too big to be used in the field, but micromotors can be as effective as the larger mechanical versions and with the added benefit of being transported almost anywhere.