Ivan Minev Group
Building interfaces between biological systems and machines
Bioelectronic interfaces are systems that exchange information between living matter and machines. They can take many physical forms such as implants residing in the nervous system, electronic circuits on skin or microphysiological platforms merged with cells or organoids. Bioelectronic interfaces are expected to become a key medical technology in the 21st century that will enable new types of prosthetics and even repair of functions lost through injury or degeneration.
Our main interest concerns building the hardware that will underpin next generation bioelectronic interfaces. The main challenge we address is the seamless merging of living matter and machine. If this can be achieved, long standing challenges relating to biointegration, reliability and limitations in the quantity and type of information exchange may be resolved.
Our work focuses on three distinct areas: new materials for bioelectronics, devices and systems and (pre)clinical translation.
Materials: inside the body bioelectronic interfaces operate in a chemically and mechanically challenging environment, should not produce adverse reactions (e.g. foreign body response) and should survive extended periods of time while maintaining functionality. We aim to address some of these challenges by engineering materials that resemble the mechanical and biochemical properties of soft tissues such as the brain and additionally transcend purely electrical or purely biological functions. This could be achieved using hydrogels possessing both electronic and ionic conductivity combined with bioactive scaffolds. Their physical and biological properties can be electrically controlled which is the basis for sensors and actuators that operate in the electrical, biochemical and mechano-biological domains.
Devices: another of our key research efforts is on adapting or inventing rapid prototyping approaches drawing on various printing and 3D printing technologies (extrusion, ink-jet and electrochemical printing). This enables different bioelectronic materials to be processed together into designs tailored to applications as devices for implants, wearables or cell culture platforms. The miniaturisation level is on the sub-mm scale.
Systems: this concerns the combination of individual devices into arrays and systems. Arrays of sensors and actuators are equipped with custom connectors and integrated with signal acquisition and control electronics to build stand-alone, sometimes even autonomous systems for deployment in biological applications.
Future Projects and Goals
In this project we will ask the question: can an entirely new set of materials help us to build electronic devices and systems that are virtually indistinguishable from living matter? We will contribute to the development of a new class of materials known as conductive hydrogels. They are soft, made from more than 90% water and can conduct both ionic and electronic charges. We will explore blending conductive polymers (e.g. polythiophenes) with biomacromolecules found in the extracellular matrix of tissues. We will explore novel monomers, polymerisation techniques to assemble the materials as well as microfabrication technologies to build simple devices. An advanced aim will be to create devices whose biological function can be switched using electronic commands. They will be tested in cell cultures or in vivo as implants.
Methodological and Technical Expertise
- 3D printing
- electrical characterisation of materials