Researchers at Georgia Tech have developed the Smart Wireless Autonomous Networking System (SWANS), an alternative to Bluetooth and NFC for in-body communication. Unlike radio-based protocols that suffer from signal attenuation in tissue and high power consumption, SWANS utilizes ionic conduction to transmit signals through body tissue, mimicking the nervous system.
The system consists of a wearable hub, a microneedle patch, and injectable implants. The hub emits voltage pulses of up to 12 volts, which travel through tissue to reach specific implants. By adjusting pulse strength and duration, the system can selectively trigger individual devices. This approach allows implants to remain in a low-power state, extending battery life by over 15 times compared to traditional radio methods.
The implants measure 3 by 1.1 by 17 millimeters and can be injected via a 6-gauge needle. Tests in pork tissue demonstrated signal coverage of over 30 centimeters across and 14 centimeters deep, significantly exceeding the range of Bluetooth. In live rat studies, the system successfully stimulated nerves and relayed temperature data between implants.
The team observed that while scar tissue up to one millimeter thick formed around the devices during a two-month study, communication remained functional by adjusting voltage levels. The researchers noted that the system does not currently support high-speed data transmission and is intended for passing specific information, such as sensor readings or trigger signals for drug delivery and neurostimulation.
While the technology has not yet been tested in humans or large animals, the developers suggest it could integrate with existing medical implants to create coordinated therapeutic networks. The protocol is designed to be agnostic to the specific sensors or actuators used, potentially enabling combined treatments for conditions like epilepsy.
