Microrobots, created by nanoengineers at the University of California, San Diego, can deliver medication, swim around in the lungs, and be used to treat life-threatening cases of bacterial pneumonia.
The microrobots successfully eradicated the bacteria that causes pneumonia in the lungs of mice, resulting in 100% survival. In contrast, mice that were not treated all passed away three days after becoming ill.
The algae cells used to create the microrobots have antibiotic-filled nanoparticles all over their surfaces. The microrobots can swim around and deliver antibiotics directly to more bacteria in the lungs thanks to the movement provided by the algae. The antibiotic-containing nanoparticles are made up of tiny biodegradable polymer spheres with neutrophil cell membranes coated on them.Neutrophils are a type of white blood cell. These cell membranes are unique in that inflammatory molecules produced by bacteria and the body’s immune system are absorbed and neutralized by them. The microrobots can do this, which enhances their ability to fight lung infection by lowering harmful inflammation.
Both Joseph Wang and Liangfang Zhang, professors of nanoengineering at the UC San Diego Jacobs School of Engineering, collaborated on the project. Wang is a global expert in the study of micro-and nanorobotics, and Zhang is a global expert in the creation of nanoparticles that mimic living cells to treat illnesses and infections. Together, they have paved the way for the creation of tiny drug-delivery robots that can be used to safely treat bacterial infections in the blood and stomach of live animals. The most recent aspect of their work involves treating bacterial lung infections.
“Our objective is to perform targeted drug delivery into the body’s more difficult areas, such as the lungs. We also want to do it in a manner that is simple, quick, biocompatible, and durable, “Zhang said. “In this work, we have shown that to be the case.”
The team treated mice with Pseudomonas aeruginosa-caused acute pneumonia using microrobots to prevent death in some cases. Patients receiving mechanical ventilation in the intensive care unit are frequently affected by this type of pneumonia. Through a tube placed in the mice’s windpipe, the researchers delivered the microrobots to their lungs. After one week, the infections were fully under control. Mice not given the microrobot treatment died after three days, while every mouse treated with them lived for more than 30 days.
A bloodstream IV injection of antibiotics was not as effective as the treatment with the microrobots. In order to achieve the same effect, the latter needed an antibiotic dose that was 3000 times higher than what was used in the microrobots. For comparison, an IV injection delivered 1.644 milligrams of antibiotics per mouse, while a dose of microrobots delivered 500 nanograms.
The team’s strategy works so well because it delivers the medication directly to the patient’s area of need rather than dispersing it throughout the body.
According to Wang, these findings demonstrate how active movement from the microalgae and targeted drug delivery can enhance therapeutic effectiveness.
Sometimes, only a very small portion of the antibiotics administered via IV will reach the lungs. Due to the fact that many current antibiotic treatments for pneumonia don’t work as well as they should, the sickest patients experience extremely high mortality rates. ” Victor Nizet, a physician-scientist collaborator of Wang and Zhang and a professor at the UC San Diego School of Medicine and Skaggs School of Pharmacy and Pharmaceutical Sciences, is a co-author of the study. According to the mouse data, the microrobots may be able to increase antibiotic penetration to kill bacterial pathogens and save the lives of more patients.
And if the idea of inhaling algae cells makes you queasy, the researchers claim that this method is secure. Following treatment, the algae and any lingering nanoparticles are effectively digested by the body’s immune cells. According to Wang, nothing hazardous is left behind.
The proof-of-concept phase of the project is still ongoing. The team plans to conduct more fundamental research to precisely understand how the microrobots interact with the immune system. Prior to testing it on larger animals and eventually on humans, the microrobot treatment will also undergo studies to validate it and be scaled up.
In the area of targeted drug delivery, “we’re pushing the envelope even further,” said Zhang.
