Researcher develops microrobots to battle cancer with unique precision

May 1, 2024

4 min

Sambeeta Das


Magnetic robots that can target cancer cells are nothing new. But the patented microrobots developed by the University of Delaware's Sambeeta Das can be guided with a magnetic field to deliver medication to cells – or to destroy infectious cells, such as cancer – inside the body.


To mark the launch of National Inventors Month, Das, assistant professor of mechanical engineering, shared her journey toward invention.


Q: Tell us about your patented invention on microrobots for cancer research. What problem were you trying to solve?


Das: One of the biggest issues with cancer research is the ability to target cancer cells without harming healthy cells. Cancer cells are sneaky, and they have evolved ways of hiding from the body’s immune cells.


A big part of our research focuses on targeting, specifically precision targeting. We want to be able to target a single cell in a mass of cells, whether that is a single cell in a mass of cancer cells or whether it is a single abnormal cell surrounded by healthy cells. To do this, we use magnetic microrobots that can be driven inside the body by magnetic fields to a particular cell location. Magnetic fields are biocompatible, meaning they are not harmful to biological tissues, and our microrobots are very small, around 20 microns, which is about the size of a single bacteria cell. We can load our microrobots with various drugs and modify their surface in such a way that when the robots come in contact with the cells we are targeting, they can kill the target cell or perform some other function.


Q: How is this solution unique?


Das: Other people have made magnetic microrobots, but our system is unique since it allows us to do automatic targeting with a lot of precision. For example, a person operating our microrobots can just point to a cell and our system will drive the microrobot there. Additionally, the instrument we have made and patented is an all-in-one portable device that can be used anywhere. We don’t need a separate microscope, camera or software, it is all built in and very user friendly. Anyone can use it. This makes it super portable, which means quick solutions for health practitioners. In addition, poor and resource challenged areas can also be accessed with this portable solution.

Q: What drives you toward invention?


Das: I like to solve problems, and I like seeing something come together from nothing. I am very interested in problems that affect human health and longevity, particularly those that affect the common person.


Q: How do you approach solving a problem, and whose support has been critical along the way?


Das: One thing I have realized is that it is imperative to ask the right question to solve a problem. You must really get to the core of the issue. The second thing is to always keep the end user in mind. So, it’s kind of a two-pronged approach—looking from both ends of the problem.


For support, I would say my team members and my collaborators. Their support has been invaluable in helping me solve the problems that I want to solve. In fact, my graduate students keep a running list of crazy ideas that they have come up with. It helps us look at problems in a unique way and come up with innovative solutions.


Q: Not every invention makes it. How do you deal with failure?


Das: The way that I start working on a problem is to assume that whatever we do, we are going to fail. I always tell my students that their first couple of experiments or designs will always fail. But failure is essential because it will teach you what not to do. And knowing what not to do is sometimes the critical part of the invention process. The failures inform us about the ways of not doing something which means now there is another way of doing something.


Q: What is the best advice you’ve ever received?


Das: The best career advice I’ve ever received is that there is always another way. If you run into roadblocks there is always another answer, there is always another opportunity. So we just need to keep going and trying new and crazy ideas.


Q: How are inventive minds created – is it innate or can it be developed? How do you encourage innovation among your students?


Das: That’s an interesting question and honestly, I am not sure. I do believe in what Edison said, “Genius is 1% inspiration and 99% perspiration.” He is a known inventor, so I would go with his interpretation on this.


As for my students, I give them lots of freedom. I think freedom is essential in encouraging innovation. The freedom to come up with crazy ideas without anyone saying that won't work and the freedom to fail—multiple times.


Das is available for interviews to talk about her microrobots and other projects at UD. To reach her, visit her profile and click the "contact" button.

Connect with:
Sambeeta Das

Sambeeta Das

Assistant Professor of Mechanical Engineering

Prof. Das’s research spans robotics, autonomous systems, physics, organic chemistry and materials engineering.

Biomechanical EngineeringClean Energy & EnvironmentMaterials EngineeringBiomechanicsFluid Mechanics

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