Researchers create prototype sponge-like sensor for personalised healthcare 

Researchers from AMBER, the SFI Centre for Advanced Materials and BioEngineering Research at Trinity College Dublin’s Centre for Biomedical Engineering, have developed a prototype wearable sensor that can be manufactured at a very low cost and accurately detects a variety of health parameters such as swallowing, muscle tensing, and limb movements.

The scalable and sustainable manufacture of wearable sensors for personal use is becoming ever more significant with the emergence of ‘Connected Health’ – a healthcare model where new technology facilitates personalised, data-driven healthcare delivery.  

The team’s approach uses a polymer called PEDOT:PSS that is commonly used as a material for electrodes and sensors because it is capable of conducting electricity. This material has been used in other sensors in the form of a thin-film or a coating but with limitations to its uses and performance. Instead, the Trinity team turned PEDOT:PSS into a 3D sponge-like structure using a process similar to freeze-drying that removes the liquid from the material and leaves behind a 3D porous structure. They found that this sponge-like structure alone can reliably detect small movements and stresses, but wanted to improve its longevity, accuracy and applicability.  

To do this the group introduced a silicone-based material into the pores, or empty spaces, in the 3D sponge-like structure. They found that the silicone-based material was very important to the overall performance of the sensor, allowing it to function for longer without deteriorating, while maintaining its all-important conductive properties. 

Their results are published in Applied Materials and Interfaces of the American Chemical Society.  

Dr Matteo Solazzo of the Trinity Centre for Biomedical Engineering, comments:  

“Wearable sensors are increasingly being explored due to the increase of Connected Health, telemedicine and personal responsibility for fitness and health. Sensors are already used for a vast range of applications from sports gear to medical devices for personalised diagnostics, and even in robotics for electronic skin and tactile sensing. Potentially, every human being will use a wearable sensor at least once in their life and as researchers we are always looking into the development of new materials and new devices, aiming to improve performance while cutting costs.” 

Prof. Michael Monaghan, AMBER, and Ussher Assistant Professor in Biomedical Engineering at Trinity, adds: 

“While most studies look into the synthesis of new materials to achieve better sensors for healthcare applications, we decided to use our expertise in creating 3D porous scaffolds and apply it to PEDOT:PSS, a well-established electroconductive polymer. By then introducing PDMS, a silicone-based compound, we found we could improve the performance of our sensor further and in very distinct, measurable ways. Our sensor is proof that 3D PEDOT:PSS scaffolds are not only candidates for superior wearable sensors, but also that our manufacturing strategy could be translated to other conductive polymers. The success achieved by my team paves the way for multiple applications and new research areas.”  

ENDS