Tiny hairlike robots could transform treatment options for chronic lung diseases

Vanderbilt scientists have created robotic cilia—similar to the vibrating hairlike structures responsible for moving viscous fluids in the lungs—that can clear mucus from airway stents used to treat conditions like lung cancer, cystic fibrosis (CF) and chronic obstructive pulmonary disease (COPD).

Xiaoguang Dong

The invention is the first of its kind and addresses the challenge of keeping commercially approved airway stents free from obstruction, said Xiaoguang Dong, assistant professor of mechanical engineering, whose lab developed the devices. The work was done in collaboration with Vanderbilt University Medical Center faculty members Fabien Maldonado, professor of medicine and thoracic surgery, and Matthew D. Bacchetta, who holds the H. William Scott, Jr. Chair in Surgery and is professor of cardiac surgery, thoracic surgery, and biomedical engineering.

Dong, a specialist in the field of soft robotics that are designed to operate inside the human body, said the smooth, hollow interiors of airway stents often lead to a significant accumulation of mucus with no way to remove it due to the blocking of biological cilia. This poses significant problems for patients suffering from severe forms of lung disease.

“This is a serious issue for these patients and our work tries to mimic the natural systems that take place in the lungs,” Dong said. “This is the first time anyone in the world has developed something like this.” The study was published online on October 31, 2023, in the journal Advanced Material Technologies. He will also present the research at the Nature conference, “Bioengineering for Global Health,” which is being held at Vanderbilt University Nov. 13-15.

The robotic cilia are made primarily of silicone rubber and magnetic particles, and are arrayed in a patch with a thickness of seven micrometers. The researchers optimized the robotic devices by applying a bio-compatible hydrogel coating—also developed by Dong’s lab—to the cilia that proved more efficient in transporting fluids of a similar viscosity to human mucus.

While Dong said he sees areas for future refinement, he and his co-authors wrote, “Our proposed ciliary airway stent (CAS) has shown unprecedented capability of transporting and removing excessive mucus in a minimally invasive manner.”

The research team is affiliated with the Vanderbilt Institute for Surgery and Engineering and included Vanderbilt Ph.D. student Yusheng Wang and School of Engineering junior, Saksham Sharma.