Impact of Operating Frequency and Substrate Materials on Microwave Sensor Sensitivity for Blood Glucose Monitoring

A biosensor is designed to detect glucose concentration levels using a single metamaterial-based asymmetric double split ring resonator. The study investigates the influence of operating frequency and substrate on sensor sensitivity. The glucose sample is placed in a small semi-circle gap within the sensor. At this location, a confined electric field enhances the sensor's sensitivity. The sensor's sensitivity has been investigated across three frequencies of 1 GHz, 3 GHz, and 7 GHz, implemented on an FR4 substrate. Additionally, the study compares the sensor sensitivity across three different substrates: Teflon, Rogers AD350A, and FR4 at 7 GHz. The results show that the sensor operating at 7 GHz is the most sensitive to the glucose concentration levels, while the sensor incorporating Teflon substrate exhibits the highest sensitivity to glucose concentration levels. The results, obtained through simulations using CST Microwave Studio, show the potential of this design for improving continuous glucose monitoring systems, a critical tool in managing diabetes.