(39g) Micropatterning of Silk Protein-Conductive Polymer Biocomposites for Fabrication of Flexible Devices

The precise micro- and nano fabrication of flexible devices using biomimetic materials has attracted significant attention owing to the potential for improved adaptability to physiological environments, as well as to form “green” devices for sustainable future. In particular, silk proteins (fibroin and sericin) are versatile materials to form flexible, biocompatible and biodegradable devices such as sensors, energy storage, and bio-microelectromechanical systems (bioMEMS). In conjunction with intrinsically conducting polymers (CPs) with their chemical diversity and ionic conductivity, the electrochemical functionalization of such biomaterials in organic bioelectronics can be enabled. In this talk, we will discuss various biodevices for sensing and energy storage that can be fabricated while retaining mechanical compliance, biocompatibility and degradability.

Biomimetic composites based on silk proteins and CPs are used to create novel photoreactive sensing inks, which are then coupled with lithographic tools to form micropatterned, organic, flexible and degradable biodevices. The biochemically modified silk proteins behave as negative-tone photoresists (fibroin and sericin photoresists) to enable accurate and high-resolution microfabrication on flexible substrates using photolithography. Optimization of the biofriendly fabrication process as well as the versatility of this biomaterial platform that can combine different CPs (e.g. PEDOT:PSS, polyaniline (PANI)) with protein microfabrication will be presented. The electrochemical characterization of the devices via electrochemical impedance spectroscopy (EIS) and other physical voltammetry techniques will be discussed towards the fabrication of microsupercapacitors and the detection of electroactive (e.g. dopamine and ascorbic acid) as well as electro-inactive (e.g. C-reactive protein) biomarkers. Importantly, the performance of the devices under mechanical flexure, and to form highly compliant, lightweight sensors that can integrate with soft interfaces will be shown. The engineered properties of these organic biocomposites provide opportunities as sustainable devices that can be programmed to resorb, adapt to the tissue or skin interface, and provide high resolution spatial and temporal sensing.