The biomarker smart ring is a fully integrated prototype that includes all the necessary biomarker sensing technology, low-power electronics and a flexible battery. Biomarker information is sent wirelessly to a smartphone app. The ring draws sweat passively using an osmotic hydrogel, a soft polymer that creates a pressure gradient to pull fluid from the skin painlessly. It works similarly to how water travels from soil to the leaves in plants. The collected sweat is analyzed by an electrochemical sensor array within the ring. Through repeated measurements, subject-specific calibration factors are established to convert current responses into concentration values. These calibration factors enable more personalized insight into the biomarker trends.<\/p>\n
The ring is powered by a flexible zinc-silver oxide rechargeable battery that supplies power for up to 12\u202fhours of operation between charges. The electronic board dimension ranges smaller than a US quarter coin. The outer shell of the smart ring is made from a 3D\u2011printed polymer. \u201cSuch integration onto the small footprint of a ring form factor is amazing,\u201d Wang said.<\/p>\n