Researchers from the University of Cambridge have developed a method to create adaptive and eco-friendly sensors that can be directly printed onto biological surfaces. Inspired by spider silk, these ‘spider silks’ are lightweight and can conform to a variety of surfaces without collapsing their structure. The fibres are at least 50 times smaller than a human hair and can be printed on human skin to monitor health continuously, without the wearer detecting their presence.
This low-waste and low-emission method has applications in fields such as healthcare, virtual reality, electronic textiles, and environmental monitoring. By printing sensors directly onto the skin, it could fundamentally change interactions with the world around us. With the goal of creating imperceptible bioelectronics that do not interfere with normal sensations, the researchers aim to create sustainable and low-waste sensors.
Existing wearable technologies with embedded sensors can be uncomfortable and obstructive, limiting the skin’s natural sensations. Flexible electronics are often printed on plastic films that do not allow gas or moisture to pass through, similar to wrapping skin in cling film. Other methods, such as spinning electronic fibres, result in imperceptible devices but lack sensitivity or sophistication. 3D printing is another option but leads to thicker devices that can interfere with normal behavior.
The researchers’ bioelectronic ‘spider silk’ is made from biocompatible conducting polymers spun from a water-based solution at room temperature. This enables control over the ‘spinnability’ of the fibres, allowing them to conform to a range of biological surfaces. Tests on human fingers and dandelion seedheads have shown high-quality sensor performance while remaining imperceptible to the host. The sensors are repairable and can be easily washed away at the end of their useful life, generating minimal waste.
The simplicity of the fabrication technique allows sensors to be placed almost anywhere and repaired as needed without the need for a big printing machine or central manufacturing facility. These sensors can be made on-demand, producing minimal waste and emissions. The researchers believe that their devices could have applications in health monitoring, virtual reality, precision agriculture, and environmental monitoring. They aim to incorporate other functional materials into the fibre printing method to build integrated sensors for living systems with display, computation, and energy conversion functions.
The research has been supported by various organizations and is being commercialized with the help of Cambridge Enterprise. By creating sustainable and adaptable sensors that can be directly printed onto a range of biological surfaces, the researchers hope to revolutionize the way we interact with electronic devices in our everyday lives.