Innovation within: Christopher Bettinger and biodegradable polymers

Prof Christopher Bettinger was recently named as one of Technology Review’s ‘innovators under 35’ for his work in developing the next generation of medical devices. We spoke to him about his influences, his innovation process and how his ‘unbridled curiosity’ has kept him supplied with ideas.

Christopher Bettinger had wanted to be a doctor for as long as he could remember. That was until a field trip when he was 15 changed everything. “During high school we visited a local hospital. I fainted in the cadaver lab and that was basically the end of my medical career.”

Yet, some 15 years later, Professor Bettinger’s work is firmly positioned in the medical sphere. And, as shown by his inclusion in Technology Review’s 2011 TR35 (a list of 35 innovators under 35 who are “tackling important problems in transformative ways”), his work has the potential to affect thousands of people’s lives.

In his laboratory in the Departments of Materials Science and Biomedical Engineering at Carnegie Mellon University, Pittsburgh, he and his three PhD students are working to develop the next generation of medical devices.

These devices will be created using electronics based on materials that exist naturally in the body, such as the skin pigment melanin. Not only will they be controllable from outside the body – allowing clinicians to decide when the device should release antibiotic or stimulate nerve growth – but the implants will also break down naturally in the body.

Unsurprisingly for someone working in a field that spans many disciplines – materials processing, electrical engineering, applied physics, biology – Bettinger says his attitude has always been based on “unbridled curiosity” across many different subjects and a need to know how things work. “If you’re curious about everything then you can populate your mind with these as-yet-unconnected notions,” he says. “If you keep learning and keep reading about things, then you can draw connections in different ways.”

Picking polymers

His interest in biology and medicine survived the trip to the cadaver lab, and influenced the direction of his early career. Part-way through a chemical engineering degree at MIT, Bettinger did an internship at Texas Instruments, who manufacture silicon semi-conductors, to study microfabrication. “I was always interested in making useful devices but I was kind of bored with their approach – they seemed focused on using the materials they had but I thought that other materials would maybe be interesting.”

Inspiration around alternative materials came during a Master’s and PhD at MIT, where Bettinger began to think about combining the fields of electronics and biomaterials.

His ideas crystallised during postdoctoral training under Zhenan Bao at Stanford University, where he studied organic electronics. Unlike silicon-based electronics, organic electronics are relatively low performance but cheap and flexible – found in things such as disposable sensors or radio-frequency identification (RFID) tags on shipping containers. Bettinger recounts a profound moment when he realised that these polymers could be made out of biodegradable materials.

Inspiring ideas

Working to create biodegradable electronics based on the body’s own molecules may seem ambitious to some – perhaps even impossible – but this doesn’t put Bettinger off. Quite the reverse. “I draw inspiration for my work from Bob Langer, my PhD supervisor at MIT. Early in his career he had this [at the time] crazy idea of being able to use polymers to deliver drugs and control the release of therapeutics. No-one believed in him, but he just powered through it, stayed with his ideas and it worked out really well for him.”

He hopes to emulate Langer’s impact on biotechnology. “Maybe the idea of making biodegradable electronic devices for medical implants is a little strange at the moment, but I like to think there’s a parallel path.”

Beyond the technical difficulties in developing new materials, Bettinger identifies another major challenge to his field. “A big issue in the US is the regulatory procedure for medical devices – that’s ultimately the bottleneck. If we’re making new materials then the US regulatory agencies see them as an unknown risk – so it’s treated like a new drug. So that’s why we’re trying to use materials that already exist in your body.”

What does he hope for in the future? “Ultimately I’m interested in making medical devices that can restore or replace functions of the human body. The trick is managing the interface between the great engineering tools we have and our cells, tissues and organs.”

It’s all a long way from the teenager who fainted at the sight of a dead body.

21/12/2011 | Posted by Medtronic
Tags: Christopher Bettinger, medical devices, innovation; polymers; organic electronics; biodegradable electronics; biotechnology; biomedical implants; biodegradable electronic devices