Engineering with heart

Daniel Roxby. Photo by Joanne Saad.

Daniel Roxby. Photo by Joanne Saad.

In summary: 
  • PhD student Daniel Roxby is developing a way to power implanted medical devices, like pacemakers and deep brain stimulators, without the need for surgery
  • His research is centred on the combination of microbial fuel cells and glucose, which is found in the human body

Biomedical technology is empowering and life-giving, but at times it can be limiting. It’s this paradox that led electrical engineering alumnus Daniel Roxby to synthesise his studies in a PhD with UTS’s Centre for Health Technologies. His aim: to enable chronically ill patients to live more enriched lives.

"We might be okay with recharging our phones every day, but there are much larger implications for health,” explains Roxby. “How can we comfortably go about our day or travel, while thinking we have to recharge the device inside us that’s helping to give us life?"

Much of Roxby’s curiosity, confidence and love for research came during his undergraduate degree at UTS, where he worked with international engineering firm Steensen Varming and the CSIRO Astronomy and Space Science division. His experience included working on an international project to build the world's largest radio telescope; consisting of thousands of antennas linked together by high bandwidth optical fibre.

"Working collaboratively with various scientists, technicians and other engineers, I was immersed in a huge variety of tasks,” says Roxby. “I had to apply my engineering knowledge and learn about various aspects of the project, not just the technical elements of engineering.  

"I was also lucky to meet inspiring friends in my undergrad years who wanted to go into professions like medicine because they did some good for society.

"Studying medical science as an engineer really fascinated me, and I discovered what an amazing work of engineering the human body is." 

In collaboration with his PhD supervisor and Director of the Centre for Health Technologies Hung Nguyen and Lecturer Nham Tran, Roxby is researching microbial fuel cells (MFCs) and how they might be able to power implanted biomedical devices like pacemakers and deep brain stimulators. MFCs traditionally use bacteria and organic matter found in sludge and wastewater to generate small amounts of electricity.

"We hope to use these and glucose – which is often found in the blood – as the food. And so far, we’ve been successful in generating small amounts of electricity by powering a simple circuit," says Roxby. 

"Originally, Daniel came up with the idea of converting human body heat into electricity to power body sensors and biomedical devices, but we were not able to gather much energy to power a device,” explains Nguyen. "Daniel's idea was a good one, since powering implanted devices is a major problem. Patients who are chronically ill often have a combination of complex health issues and device batteries need to be replaced surgically."

Roxby’s area of research is unique. There are approximately three major lab groups working on MFC technology internationally, but a lot of their recent work has been in up-scaling wastewater MFCs or understanding why certain bacteria generate more electricity than others.

"I want to push the technology to its use for small scale electronics,” says Roxby. “This would mean, at the very least, miniaturising it whilst still maintaining reasonable power outputs. I would also like to be able to lengthen the power output time, using small amounts of sugar, so if we get to implant such a technology in future, we wouldn’t need to continuously replenish it.

A humble Roxby adds, “These are reasonable first steps to really enabling people with biomedical devices to live their lives more freely."