Voice Prosthesis Implantable UHF RFID Self-Sensing Tag for Microbial Growth Detection

Passive Radio Frequency Identification (RFID) implantable antennas experience low efficiency due to the capacitive loading of human tissue that the implantable design has to overcome. Here we present a passive UHF implantable device able to produce a read range of 65 cm (EU frequency band) and 80 cm (US frequency band) from within the body. With a slight adjustment, this self-sensing tag can be utilized to sense microbial growth within the body once mounted upon a voice prosthesis. Simulated Candida albicans biofilm growth can be detected within the body with this sensor from early and up to a mature biofilm thickness of 30 µm (0 to 48-hour growth in vitro equivalent); allowing for detection before any infection symptoms within a patient become apparent (as early as 4-hour biofilm colonization (5 µm thickness)) and before the voice prosthesis experiences failure. This passive UHF device would permit cost-effective immediate medical intervention before any serious consequence could occur to a voice prosthesis patient.