While currently available wearables rely on monitoring physiological parameters such as the heart rate, an in-depth analysis requires continuous quantification of molecular biomarkers, which naturally entails direct contact with the user’s biofluids. To that end, blood is generally regarded as the gold reference biofluid, but blood sampling is an invasive technique that is incompatible to the needs of wearables users. In ELSAH, we targeted minimally invasive sampling of the dermal interstitial fluid (ISF), which has been proven to be highly similar in biomarker composition to blood. In addition, the probing of ISF by microneedles has been validated as pain-free. By enabling molecular detection in the ISF, we realized a wearable that provides truly evidence-based support to healthy living. This leads to better health and well-being, which in turn can be expected to also cause a reduction in the prevalence of diseases of affluence like obesity, cardiovascular diseases, high blood pressure or type 2 diabetes.
The overall objective of ELSAH was to realize a flexible and integrated smart patch-based wearable sensor system (‘ELSAH-patch’) that quantifies several molecular biomarkers in parallel by minimally invasive microneedle-based sampling and electrochemical detection. The ELSAH-patch is fully self-sustained by integrating the microneedle biosensor with microchip, battery and electronics (interconnects and antenna structures), thereby enabling independent measurements and secure wireless data transmission to the user’s mobile phone. To demonstrate our ELSAH-patch, we chose the two biomarkers glucose and lactate, which are amongst the most established and prominent biomarkers to support a healthy lifestyle.
Two separate ELSAH-patch demonstrators were developed and evaluated in the project:
• A clinical study demonstrator (codename Graz) aligning with key medical device regulations and used for first-in-human trials. The developed components biosensor and microchip were integrated with commercial solutions for batteries (coin cells), antenna and interconnects (PCB technology).
• A technology demonstrator (codename Vienna), which integrated all the technology and scientific modules (including printed battery and printed electronics) into a functional non-clinical device evaluated in a laboratory environment.
The ELSAH project brought together eleven leading partners from five European countries, including three research institutions, three universities and five companies (two large companies and three SMEs).
