Research Highlights

doi:10.1038/nindia.2017.65 Published online 12 June 2017

Silk protein for making biophotonic devices

Researchers have synthesized a silk-protein-based hybrid material whose sensitivity to optical signals1, makes it potentially useful for making biophotonic devices. 

Flexible and stretchable electronic and photonic devices have many optoelectronic and biomedical applications. But, silicon-based devices are not mechanically stable and are not suitable for biocompatible implantable devices. Natural silk protein fibroin, however, is one of the most widely used insulating biopolymer material.

To make biocompatible photonic devices using silk protein, scientists, led by Subhas Kundu and Samit Ray from the Indian Institute of Technology, Kharagpur prepared the hybrid material by depositing zinc oxide nanorods on a nanocomposite film made of silk protein fibroin and gold nanoparticles.

The presence of gold nanoparticles made the hybrid material sensitive to both ultraviolet and visible light and this property was exploited to make a photodetector which showed higher sensitivity than one based on zinc-oxide.

The hybrid-material-based devices fabricated on plastic substrates were found to be flexible, retaining  their stability and efficiency even after being bent and stressed at different angles.  The work also reveals novel light-induced electrical properties in the silk-based hybrid material, which could be useful for making self-powered photodetector devices.

The hybrid material could potentially be used to make textile-based smart electronic devices for defence purposes, the researchers suggest.


References

1. Gogurla, N. et al. Gold nanoparticle-embedded silk protein-ZnO nanorod hybrids for flexible bio-photonic devices. Nanotechnology. 28, 145202 (2017)