Bacterial shell protein shows promise for safe, wearable electronics

A team of Indian scientists has discovered a semiconductor-like property in a self-assembling bacterial shell protein that could pave the way for safe, environmentally friendly wearable and implantable electronic devices.

Researchers at the Institute of Nano Science and Technology (INST), Mohali in Punjab, have discovered that the protein can act as a light-driven semiconductor without the need for added dyes, metals or external power sources, according to officials from the Ministry of Science and Technology.

Conventional semiconductor materials such as silicon are valuable technological tools that have their own limitations because they are rigid, require energy-intensive manufacturing and add to the growing burden of electronic waste. At the same time, demand is rising for sustainable, flexible and biocompatible electronics, particularly for wearables, medical implants and green sensors.

The INST team, led by Dr Sharmistha Sinha along with student researchers Silky Bedi and S M Rose, investigated whether bacterial shell proteins, which naturally self-assemble into large, stable, 2D sheets could be intrinsically photoactive. The proteins possess built-in electron density patterns and aromatic amino acids that suggest potential electronic behaviour.

The researchers found that when the proteins form thin, flat films, they absorb ultraviolet (UV) light and generate an electrical current. The effect arises from tyrosine, a naturally occurring amino acid in the protein, which releases electrons when excited by light.

As electrons and protons move across the ordered protein surface, the sheet produces an electrical signal, functioning in a manner similar to a miniature solar cell. Crucially, this light-driven response depends solely on the protein's internal structure and does not require synthetic additives or high-temperature processing.

According to the researchers, the findings open up multiple application possibilities. Because the material is flexible and biocompatible, it could be used in wearable health monitors, skin-safe UV detection patches and implantable medical sensors designed to operate safely inside the human body.

The protein-based material could also be used in temporary or disposable environmental sensors, such as pollution monitors or sunlight trackers, which would naturally degrade after use without harming the environment.

The study by the researchers, published in the journal Chemical Science of the Royal Society of Chemistry, represents a promising step toward bio-inspired electronics, where materials are designed by learning directly from the ingenious mechanisms found in nature. Such materials could lead to a new generation of electronic technologies that are not only functional and efficient, but also sustainable, safe, and aligned with the needs of both people and the planet.