Engineers at Lehigh University have uncovered an unexpected motion in drug-delivery robots, which could revolutionize targeted therapy. Their findings, published on July 6, 2026, detail how these tiny robots navigate through bodily fluids, a crucial step towards precise drug delivery.
Understanding Drug-Delivery Robots
The research team, led by Ebru Demir, an assistant professor of mechanical engineering, collaborated with researchers from Santa Clara University and Brown University. They aim to develop tiny swimming robots capable of delivering medication directly to affected areas within the human body, such as delivering chemotherapy drugs to tumors while sparing healthy tissue.
According to Amin Balazadeh Koucheh, a Ph.D. student and lead author of the study, “We found that the rheology, or properties of the fluid, affected the locomotion of the swimmers.” This insight is critical as it helps researchers understand how these robots can be controlled in complex biological environments.
Challenges in Navigating Bodily Fluids
One major challenge lies in the nature of bodily fluids, which are often non-Newtonian. This means their viscosity changes when a force is applied, unlike Newtonian fluids such as water. The researchers tested the robots in both Newtonian and synthetic non-Newtonian fluids to observe their movements.
In their experiments, the team discovered that increasing the actuation frequency caused the robots to move in unexpected ways. In a synthetic non-Newtonian fluid, the swimmers exhibited a backward-sliding motion, which was not observed in Newtonian fluids. Ben Ratnor, a co-first author, described this as “almost like changing the fluid changes where the finish line is for each swimmer.”
Implications for Targeted Drug Delivery
The implications of these findings are significant for the future of targeted drug delivery systems. Understanding how the rheology of fluids affects the motion of the swimmers is essential for developing effective control mechanisms. “Both types of swimmers showed this backward-sliding motion,” Balazadeh Koucheh noted. “It’s a very nice finding since our aim is to control these swimmers inside shear-thinning fluids like mucus and blood.”
Future research will focus on microscale swimmers and different shapes to further explore the effects of fluid dynamics on their movement. Although practical applications of this technology are still years away, these incremental advances are crucial for transitioning from theoretical concepts to real-world medical solutions.
“The same swimmer behaves completely differently depending on what it’s swimming through, and that’s a powerful handle for control,” Demir concluded. “Now we're starting to see it as part of the machine.”
🤖 This article was rewritten by Feed and Figures' editorial AI from a report originally published by Phys.org. Facts and quotes are preserved from the original; the rewrite focuses on clarity and structure. For the unedited original, see the source link below.
