A fundamentally new approach for the development of EM-based implantable sensor and initial in vivo evaluation for continuous glucose monitoring is presented in this work. To the best of our knowledge, proposed sensor is first of its kind subcutaneously implantable EM-based glucose sensor capable of continuous tracking of real-time BGL. The proposed sensor utilizes strong oscillating nearfield to detect minute changes in dielectric permittivity of interstitial fluid (ISF) and blood due to changes in BGL. A biocompatible packaging material is used to cover the sensor. It helps in minimizing foreign body reactions (FBR) and improves stability of the sensor.
The performance of the proposed sensor was evaluated on live rodent models (C57BL/6J mouse and Sprague Dawley rat) through intravenous glucose tolerant test (IVGTT) and insulin tolerance test (ITT). Proposed sensor could track real-time BGL change measured with a commercial blood glucose meter. High linear correlation (R2 > 0.9) with measured BGL was observed during in vivo experiments.
An algorithm is also developed to reduce noise from the sensor data and calculate relative frequency shift from a reference point. A regression model converts this to real time BGL. Present work offers a new perspective towards development of long term CGM system using EM-based implant sensor.