Scientists at the University of Sussex have developed biodegradable algae-based hydrogels for strain-sensing devices, such as those used in health monitors worn by runners and hospital patients to track heart rate. Using natural elements like rock salt, water, and seaweed, combined with graphene, the sensors are fully biodegradable, making them more environmentally friendly than commonly used polymer-based hydrogels.
Their natural composition places them within the emerging scientific field of edible electronics, which refers to electronic devices that are safe for a person to consume. Furthermore, the researchers found that their sustainable seaweed-based sensors outperform existing synthetic-based hydrogels and nanomaterials in terms of sensitivity, improving the accuracy of the readings.
The thought to use seaweed in a health monitoring device came when lead scientist Dr Conor Boland, a physicist at the University of Sussex, was watching television during the lockdown. Seaweed is primarily an insulator, but by adding a critical quantity of graphene to a seaweed mixture, the scientists were able to create a film having electrical conductivity.
When soaked in a salt bath, the film rapidly absorbed water, resulting in a soft, spongy, electrically conductive hydrogel.
Dr Boland stated, “For me, one of the most exciting aspects of this development is that we have a sensor that is both fully biodegradable and highly effective. The mass production of unsustainable rubber and plastic-based health technology could, ironically, pose a risk to human health through microplastics leaching into water sources as they degrade.
As a new parent, I see it as my responsibility to ensure my research enables the fulfillment of a cleaner world for all our children.”
The potential benefits of this technology are significant as future applications of the clinical grade wearable sensors would look something like a second skin or a temporary tattoo: lightweight, easy to apply, and safe, as they compose of all-natural ingredients.
This would significantly help in improving the overall experience of patients, as the need for more commonly used and potentially invasive hospital instruments, wires, and leads would be eliminated.
Dr Sue Baxter, Director of Innovation and Business Partnerships at the University of Sussex, is excited about the potential benefits of this technology, stating, “At the University of Sussex, we are committed to protecting the future of the planet through sustainability exploration, expertise and innovation.
What’s so exciting about this development from Dr Conor Boland and his team is that it manages to be all at once, truly sustainable, affordable, and highly effective — out-performing synthetic alternatives.”
This latest research breakthrough follows the publication of a blueprint for nanomaterial development from Sussex scientists in 2019, which presented a method for researchers to follow to optimize the development of nanomaterial sensors.
Kevin Doty, a Masters student in the School of Mathematical and Physical Sciences at the University of Sussex, who worked on the findings under Dr Boland’s supervision, stated, “Learning about nanoscience showed me just how diverse and multidisciplinary the field is.
Any science background can bring knowledge that can be implemented to this field in a unique way. This has led to further studies in a PhD curriculum, opening up an all-new career path I could not have considered in the past.”
The development of biodegradable seaweed-based sensors offers a promising alternative to synthetic-based health monitoring devices. The use of all-natural ingredients makes them environmentally friendly and safe for consumption, while their high sensitivity offers improved accuracy in measuring vital signs.
This research offers a glimpse into a future where health monitoring technology is more sustainable, affordable, and highly effective.