Towards low-cost, wireless blood anomaly sensing: An RFID-based anemia detection sensor

Paper based diagnostic devices have great potential in the low-cost sensing of blood diseases. However, patient blood testing using these devices is limited by tedious manual intervention and qualitative colorimetric readouts. We present the novel design of an RFID-based anemia detection sensor that integrates a paper-based diagnostic device with a passive Ultra High Frequency (UHF) RFID tag. Differences in red blood cell (RBC) count in a patient's blood manifests itself as a controlled time-dependent change in the tag's signal response. We demonstrate that our sensor is capable of reliably differentiating between blood having 20, 30, 40 and 50% RBC concentration by volume - indicative of anemic vs. healthy blood. Furthermore the sensor can be read using off the shelf RFID equipment allowing for automated screening of blood specimens at large scale. Challenges in sensor design and future research directions are also discussed.