Stretchable microelectronic fibers and their assemblies as multifunctional bioelectronic interfaces for whole organs

A method of making an implantable apparatus for interfacing with an organ, the method comprising:

• forming a preform comprising an elastomeric core and a sacrificial outer layer, the elastomeric core defining a hollow channel;
• drawing the preform to form an elastomeric fiber having the hollow channel oriented along a length of the elastomeric fiber;
• removing the sacrificial outer layer from the elastomeric fiber;
• disposing liquid metal in the hollow channel;
• forming an electrical connection between the liquid metal and a microelectronic component, the microelectronic component in electrical communication with the liquid metal and adapted to stimulate and/or sense the organ in response to an electrical signal and/or electrical power conducted by the liquid metal;
• and
• integrating the elastomeric fiber with an elastomeric substrate, wherein integrating the elastomeric fiber with the elastomeric substrate comprises:
• disposing the elastomeric fiber in a channel formed on a surface of the elastomeric substrate;
• and
• disposing a plurality of layers over the elastomeric substrate and the channel.

A multi-layer implantable apparatus for interfacing with an organ, the multi-layer implantable apparatus comprising:

• an elastomeric substrate with a groove extending along an outer surface of the elastomeric substrate;
• a microelectronic fiber disposed in the groove, the microelectronic fiber comprising a liquid metal conductor;
• a plurality of layers disposed over the outer surface of the elastomeric substrate and sealing the microelectronic fiber in the groove;
• and
• at least one of a sensor or an actuator disposed on an outer surface of the multi-layer implantable apparatus and electrically coupled to the microelectronic fiber, to stimulate and/or sense the organ in response to an electrical signal and/or electrical power conducted by the liquid metal conductor.