Scientists create 'living bioelectronics' that can sense and heal skin

For years, scientists have  been learning how to integrate the world of electronics—rigid, metallic, bulky—with the world of the body—soft, flexible, delicate. In their latest work, they have created a prototype for what they call "living bioelectronics": a combination of living cells, gel, and electronics that can integrate with living tissue.

Their study was published May 30, 2024 in Science.

The patches are made of sensors, bacterial cells, and a gel made from starch and gelatin. Tests in mice found that the devices could continuously monitor and improve psoriasis-like symptoms, without irritating skin. This is a bridge from traditional bioelectronics, which incorporates living cells as part of the therapy.

Pairing electronics with the human body has always been difficult. Though devices like pacemakers have improved countless lives, they have their drawbacks; electronics tend to be bulky and rigid, and can cause irritation. But some labs specialize in uncovering the fundamental principles behind how living cells and tissue interact with synthetic materials;  previous work has included a tiny pacemaker that can be controlled with light and strong but flexible materials that could form the basis of bone implants.

In this study, they took a new approach. Typically, bioelectronics consist of the electronics themselves, plus a soft layer to make them less irritating to the body.

They wondered if they could add new capabilities by integrating a third component: living cells themselves.

They were intrigued by the healing properties of certain bacteria such as S. epidermidis, a microbe that naturally lives on human skin and has been shown to reduce inflammation.

They created a device with three components. The framework is a thin, flexible electronic circuit with sensors. It is overlaid with a gel created from tapioca starch and gelatin, which is ultra soft and mimics the makeup of tissue itself. Lastly, S. epidermidis microbes are tucked into the gel.

When the device is placed on skin, the bacteria secrete compounds that reduce inflammation, and the sensor monitors the skin for signals like skin temperature and humidity.

In tests with mice prone to psoriasis-like skin conditions, there was a significant reduction in symptoms.

The device can be freeze-dried for storage and easily rehydrated when needed.

Since the healing effects are provided by microbes, "It's like a living drug—you don't have to refill it.

In addition to treating psoriasis, the scientists can envision applications such as patches to speed wound healing on patients with diabetes.

They also hope to extend the approach to other tissue types and cell types.

Jiuyun Shi et al, Active biointegrated living electronics for managing inflammation, Science (2024). DOI: 10.1126/science.adl1102