Immune-compatible Designs of Electronic Polymers for Implantable Devices with Suppressed Foreign-Body Responses

PART 1: NON-TECHNICAL SUMMARY

Electronic biomaterials have been more and more heavily used in/as bioimplants to directly interface with biological systems, inside live human and animal bodies. The resulted devices typically provide unparalleled functions in recording, studying and modulating biological processes and physiological conditions. However, the functional longevity of these materials under bio-implantation is commonly limited by the foreign-body responses elicited by immune systems.

The material improvements for solving this problem, though highly desired, have been largely hindered by the lack of fundamental knowledge about the immune behavior at such material-biology interfaces, particularly with the influences from different material structures. In this research, aiming at closing this gap on electronic polymers—an emerging class of electronic material with higher mechanical compatibility with biological systems, Dr.

Wang proposes to carry out fundamental biomaterial research on their interaction behaviors with immune-systems, especially at the cellular level. Dr. Wang will create electronic polymers with varied chemical structures, and perform in vitro cell experiments to characterize their interaction behaviors with different types of immune cells and environment during the typical foreign-body response process.

This research will provide essential data for understanding the influence of different material design features on immune reaction pathways, and therefore guide the future development of immune-compatible electronic polymers. The research activities will provide learning and training opportunities for students at the interface of polymer science, electrical engineering, and immunology.

Supported by this research project, a new program will be established with high schools in Chicago’s south side community to bring both high school teachers and students into the biomaterials research. The research and education results will be disseminated broadly through peer-reviewed publications, seminars, conference presentations, and websites.

PART 2: TECHNICAL SUMMARY

For bioimplants that directly interface synthetic materials with biological cells and tissues in live biological systems, a long-standing challenge to be resolved is the commonly existing foreign-body responses elicited by immune systems. An emerging and promising direction for solving the immune-compatibility problem for implantable electronics is to use electronic polymers that have better mechanical compatibility with biological tissues.

However, progress has been hindered by the lack of understanding and strategies for effectively combining molecular designs for immune-compatibility and electrical conduction on polymeric materials, without sacrificing the other. This research aims to establish the fundamental biomaterial understanding about the interaction behaviors between electronic polymers of varied conjugated backbones and side-chain structures with proteins and different immune cells that make the overall foreign body responses.

Specifically, the study will include both commonly used design units for conjugated polymers, and newly incorporated immune-compatible groups for the possible improvement of immune-compatible properties. At the same time, for such new immune-compatible designs of electronic polymers, studies will also be carried out on their structure-property relationships in both electron and ion transport.

The outcome of the research can be expected to initiate a new research direction for the field of biomaterials, which focuses on combining high electronic performance and immune compatibility in a single material. Broadly, this research will make the groundbreaking steps for realizing long-term biocompatible electronic polymers, which will largely benefit the technological areas of implantable electronics for medical diagnosis, disease treatment and biological studies.

This interdisciplinary research will provide training opportunities for students at different stages for becoming the future workforce in the emerging area of biomaterials and electronics.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.