Low-Frequency Wireless Sensor Monitors Arterial Stiffening and Blood Pressure

Arteriosclerosis, the hardening or narrowing of blood vessels, complicates hemodynamic assessment and heightens cardiovascular risk. Continuous, noninvasive tracking of arterial stiffness and pressure dynamics could improve monitoring but many wireless sensors operate at megahertz-range frequencies that raise electromagnetic interference and potential tissue‑heating concerns. These limitations undermine stability and safety in clinical environments. To help address this challenge, researchers have developed a low‑frequency wireless sensing platform that captures subtle vascular pressure fluctuations in real time while reducing interference.

WiLECS (Wireless Ionic‑Electronic Coupling System) is a low‑frequency wireless electrochemical sensing platform created by a joint team at the Korea Advanced Institute of Science and Technology (KAIST) and Hanyang University. The platform combines ion‑based materials with wireless power transfer using a resonant inductor‑capacitor (LC) circuit. It is designed to operate stably at low frequencies within the human body.

The Hanyang University group developed a biocompatible ionic material with high capacitance by leveraging ion movement to store electrical charge. The KAIST team integrated this material with a wireless LC resonance system so that pressure‑induced capacitance changes can be detected remotely. Ions are tethered to gold nanoparticles and are released only when pressure is applied, producing large shifts in electrical storage from minor stimuli that are read out as frequency fluctuations.

The system maintains excellent performance below 1 megahertz and achieves a high signal‑to‑noise ratio due to reduced electromagnetic interference. In an artificial blood vessel model, the sensor monitored real‑time blood pressure changes associated with arteriosclerosis. The research was published in Nature Communications.

The work departs from the conventional strategy of increasing operating frequency to boost sensitivity. Instead, it alters the physical operating mechanism to prioritize electromagnetic safety and stability. The approach is described as opening a path toward next‑generation bio‑devices for cardiovascular monitoring.

“This research is a result of a collaborative effort combining ionic materials and wireless technology, overcoming the limitations of existing high-frequency wireless sensors. It has great potential for expansion as a platform that enables stable wireless sensing while minimizing electromagnetic impact,” said Professor Seungyoung Ahn, KAIST Cho Chun Shik Graduate School of Mobility.

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KAIST Department of Chemical Engineering
Hanyang University.