Project Spotlight: Ingestible Impedance Sensors

Eosinophilic esophagitis (EoE) is an inflammatory disorder of the gastrointestinal tract that can cause persistent feeding problems, vomiting, and abdominal pain. Currently, diagnosis of EoE is invasive and time consuming, usually involving a process to rule out other conditions with similar symptoms, such as gastroesophageal reflux disease (GERD), and the performance of an upper endoscopy to collect a tissue sample for pathological assessment. It is not possible for patients or their physicians to monitor progression of disease or response to interventions with high frequency. An ingestible sensor may provide a faster, more convenient alternative to biopsies for diagnosing and monitoring esophageal disorders, such as EoE.

Please share a little about your background and your research experiences.

Christopher Bettinger is a Professor at Carnegie Mellon University (CMU) in the Departments of Materials Science and Engineering and Biomedical Engineering. He directs the laboratory for Biomaterials-based Microsystems and Electronics at CMU, which designs materials and interfaces to integrate medical devices with the human body. Chris has published over 80 articles and has been issued over 10 patents. Chris has received honors including the National Academy of Sciences Award for Initiatives in Research, the MIT Tech Review TR35 Top Young Innovator under 35, and the DARPA Young Investigator Award. Professor Bettinger is also a co-inventor on several patents and Co-Founder and CTO of Ancure, an early-stage medical device company. Professor Bettinger received a S.B. in Chemical Engineering, an M.Eng. in Biomedical Engineering, and a PhD in Materials Science and Engineering as a Charles Stark Draper Fellow – all from the Massachusetts Institute of Technology. He completed his post-doctoral fellowship at Stanford University in the Department of Chemical Engineering as an NIH Ruth Kirschstein Fellow.

The mission of the Bettinger Group at CMU is to design, synthesize, and process synthetic polymers into medical devices for use in neurotechnology and beyond. We bring to bear expertise in polymeric biomaterials and flexible electronics for use in next-generation medical devices that can integrate seamlessly with tissues in the human body. We work towards this goal by investigating fundamental properties of polymers and then applying these discoveries to design new types of flexible electronic devices. If successful, the innovations in materials and devices could fundamentally improve our ability to sense and modulate organ systems, diagnose disease, or administer new treatment paradigms. Towards these goals, Professor Bettinger received formal training in the following areas: synthesis and microfabrication of biodegradable elastomers; design, manufacturing, and testing of flexible electronic devices.

What led you to the PHDA?

The impact of data on health is self-evident. I am continuously inspired by my colleagues and collaborators at CMU and Pitt that parse large data sets and convert this information into actionable insight. As a materials scientist and biomedical engineer, I was interested in contributing to this vibrant intellectual ecosystem. One of the ways that I thought I could advance this broader effort is to design and fabricate new types of sensors that can generate new and interesting data sets that may not necessarily be accessible using currently available technologies such as mobile phones or wearable devices. Specifically, we are interested in designing ingestible electrical sensors that can monitor inflammatory diseases of the esophagus in a longitudinal manner.

Walk us through your project.

Like many medical innovations, the idea of an ingestible sensor is not new. In fact, there are reports of ingestible electronic sensors as early as the 1950s. Ingestible sensors have been previously designed to monitor luminal pH, core body temperature, and other physiological markers. In our project, we are interested in measuring physical properties of the esophageal tissue, some of which are reliable biomarkers for a debilitating inflammatory disease called eosinophilic esophagitis (EoE). Patients that suffer from EoE develop immense pain and have difficulty swallowing which greatly impacts quality of life. While the origin of EoE in patients is unknown, there is great value to longitudinal monitoring of this disease in patients. In our project, we aim to use ingestible devices to monitor disease progression and give patients better insight into managing their symptoms. The key insight is that our ingestible devices are made from novel materials and form factors that allow self-administration and therefore pose negligible risk to patients. If successful, our cost-effective approach can offer numerous benefits compared to painful and costly biopsies, the current standard of care. Furthermore, if these devices gain broad acceptance, we’ll be able to create large data sets that correlate EoE disease states with lifestyle choices, which could ultimately demystify the cause of EoE.

What are your project’s next steps?

We are grateful for the funding from the PHDA! The resources provided to us generously from the PHDA has allowed us to design and manufacture prototype devices. We hope to test some prototype devices in humans in the next 12 months in coordination with Kevin McGrath, MD, gastroenterologist at UPMC and Director of the GI Endoscopy Lab. We plan to parlay initial results from prototypes into a much larger project.

In what ways has UPMC played a role lending clinical expertise and sharing data?

Our project is, at its core, a hardware project. In that sense, we are excited about the prospects of generating new and interesting data sets in humans. To that end, UPMC has been instrumental in linking our group up with clinical collaborators such as Dr. McGrath. Understanding the clinical problems and the needs of the end-user can help us accelerate the design process. Furthermore, UPMC and the PHDA have brought to our attention various external funding opportunities that will be critical for expanding the project.