Scientists from the department of NanoEngineering at the University of California San Diego were able to successfully use chemically-powered micromotors to deliver antibiotics in the gut of a mouse and treat a gastric bacterial infection. It is the first use of such technology in a living organism and could pave the way for further applications in treating various types of diseases. The study was published in Nature Communications.
The bacteria that caused the infection is called H.pylori – a common type found in the digestive tract of more than half of all people in the world. H.pylori can cause ulcers in the stomach and the small intestine as well as gastritis. The bacteria is capable of living in the acidic environment of the stomach and can also penetrate the stomach lining where immune cells are not capable of reaching it.
The acidic environment of the stomach and the location of the bacteria makes antibiotic treatment difficult. Antibiotics have to be administered with proton pump inhibitors (PPIs) to reduce the production of gastric acid and preserve the effectiveness of the drugs. Unfortunately, the use of PPIs can cause other problems in the long term, like headaches, diarrhea and even anxiety and depression. This is why a treatment that can effectively deliver the antibiotics without the use of PPIs could be very beneficial.
The scientists created tiny motors made of a spherical magnesium core, covered with several layers. One layer carried the antibiotic and another enabled adhesion to the stomach wall, enabling localized delivery. The motors were propelled by the stomach acid, which was used as a fuel via a chemical reaction. This reaction also temporarily reduced the acidic environment.
The treatment proved more effective than regular antibiotic treatment. In addition, stomach pH was restored within 24 hours, while the motors themselves dissolved, leaving no signs of toxicity.
According to the researchers, this study and its favorable results open the door to the use of synthetic motors to deliver treatments for other diseases as well.