Researchers at Northwestern University developed a bioelectric implant that can detect temperature fluctuations that typically happen right before a body rejects an organ transplant. The sensor is smaller than a fingernail, and a mere 220 micrometers thick.
This new sensor technology is thin enough to sit directly on a kidney's fibrous layer — called the renal capsule — which surrounds and protects the organ. The device works by continuously monitoring changes to blood flow and temperature. The built-in thermometer can sense increases as minuscule as 0.004 degrees Celsius. Once an irregularity is detected, the sensor, which contains a micro coin cell battery for power, uses Bluetooth to alert a patient or physician via a smartphone or tablet. Any increase typically signals inflammation which is a potential sign of transplant rejection.