Tiny swimming robots help mice get rid of deadly bacterial pneumonia in their lungs

Microrobots, created by nanoengineers at the University of California, San Diego. Tiny swimming robots can carry medication, and swim around in the lungs, and these robots sort bacterial pneumonia which is life-threatening. The microrobots successfully eradicated the bacteria that causes pneumonia in the lungs of mice, resulting in 100% survival.

In contrast, mice that weren't treated all passed away three days after becoming ill. Nature Materials reported the findings on September 22. The amount of antibiotics required is a tiny portion of what is routinely used to treat this infection. The tiny robots are constructed from algal cells, which give them the ability to move, and then coated in nanoparticles containing antibiotics. The neutrophils' cell membranes, a type of white blood cell that fights infection and inflammation, are coated on the tiny spheres used to make these nanoparticles, which increases the efficiency of the swimming robots in combating lung infection.

Professor Joseph Wang, the paper's principal author, speaks to us about the technology that enabled the group of nanoengineers to build these tiny robots. 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 resemble living cells to treat illnesses and infections. Together, they have paved the way for the creation of miniature drug-delivery robots that can be used to safely treat bacterial infections in the blood and stomach of living animals. The most recent aspect of their work involves treating bacterial lung infections.

"Our objective is to perform targeted medicine delivery into harder-to-reach areas of the body, such as the lungs. And we want to accomplish it in a way that is long-lasting, straightforward, safe, and biocompatible," added Zhang. "In this work, we have shown that to be the case."

The scientists 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 catheter placed in the mice's windpipe, the researchers delivered the microrobots to their lungs. After one week, the infections were entirely under control. While untreated mice perished within 3 days, all mice treated with the microrobots did survive for more than 30 days.

A bloodstream IV infusion of antibiotics was not as effective as the treatment with the microrobots. To accomplish the same impact, the latter needed an antibiotic dose that was 3000 times larger than what was employed in the tiny swimming robots. For instance, 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.

These findings demonstrate how active mobility from the microalgae and focused medication delivery might enhance therapeutic effectiveness, according to Wang.

Sometimes, very little of the antibiotics administered by IV injection will reach the lungs. Because of this, many of the current antibiotic treatments for pneumonia don't work as well as they should, which causes extremely high mortality rates in the sickest patients, according to Victor Nizet, a professor at the UC San Diego School of Medicine and Skaggs School of Pharmacy and Pharmaceutical Sciences and a co-author on the study with Wang and Zhang. The microrobots may be able to increase antibiotic penetration to kill bacterial infections and save the lives of more people, according to the mice study.

And if the idea of inhaling algae cells makes you queasy, the researchers claim that this method is secure. Following therapy, the algae and any lingering nanoparticles are effectively digested by the body's immune cells. Nothing hazardous is left behind, according to Wang.

The proof-of-concept phase of the project is still ongoing. To precisely understand how the microrobots interact with the immune system, the team plans to conduct further fundamental studies. Before testing it on larger animals and eventually on humans, the microrobot treatment will also undergo research to validate it and be scaled up.

"In the area of targeted medicine delivery, we're pushing the boundaries even further," added Zhang.