# Silk Fibroin Protective Coating for Washable and Reusable Textile Electronics

## TL;DR

This paper introduces a silk fibroin coating that protects wearable electronics on fabric, making them washable and reusable.

## Contribution

A novel silk fibroin coating is developed to preserve electroconductive nanomaterials on fabric while enabling washability.

## Key findings

- Silk fibroin coating prevents electroconductive nanomaterials from being washed out.
- The coated fabric maintains low electrical resistance after washing.
- The coating is biocompatible and suitable for wearable devices.

## Abstract

In this study, a new way of protecting textile wearable electronics is proposed. A natural product, silk fibroin, known for its high biocompatibility, biodegradability, and low cytotoxicity, was selected to cover the functionalized fabric to improve its stability and enable washability. Silk fabric was selected as a non-toxic material, suitable for further application on skin and for wearable devices. Silk fabric was functionalized with various amounts of high-pressure carbon monoxide single-walled carbon nanotubes (HiPCO SWNTs). HiPCO SWNTs made the fabric electroconductive, but they are easily washed out of the fabric. The fabric functionalized with HiPCO SWNTs was covered with silk fibroin (SF) protein, which was subsequently crystallized by ethanol vapor to make it insoluble in water. The functionalization and silk fibroin coverage processes were studied using electrical resistance measurements, infrared and Raman spectroscopies, thermogravimetric technique, and surface wettability analysis. The coverage of the fabric with crystallized silk fibroin enables the washing process. The resistance of the functionalized fabric with silk fibroin did not increase significantly. The presented silk fibroin coating can facilitate the construction of future wearable electronics, protect the electroconductive nanomaterials on the fabric surface, and make textile structures reusable.