Flexible biomedical RF sensors to quantify the purity of medical grade glycerol and glucose concentrations

Abstract

A novel flexible radio frequency (RF) sensor is designed to facilitate the accurate testing of various samples used in the biomedical industry at the industrial, scientific and medical (ISM) frequency band. The proposed RF biosensor comprises a liquid channel-loaded interdigitated capacitor, which is integrated on a coplanar waveguide structure. The prototype of the sensor is fabricated on a 0.13 mm thin biodegradable polyethylene terephthalate polyester film to perform the testing of various bio-graded samples by recording the corresponding resonant frequency. It is observed that there is a noticeable change between the measured resonant frequencies of these samples, which primarily occurs due to the difference in their dielectric properties. The designed sensor was used to monitor and investigate the quality of glycerol, which is the most commonly used raw ingredient in the biomedical and food industry. The determination of glucose concentration in base fluids is considered to ease the challenges faced by doctors and biochemists regarding the monitoring of glucose concentration. It is found that the proposed sensor can quantify the glycerol purity up to the minimum specified adulteration level of 2 and 1% corresponding to toxic contaminants diethylene glycol and ethylene glycol, respectively, and the glucose concentration of 0.5 mg/ml.

Review of Recent Microwave Planar Resonator-Based Sensors: Techniques of Complex Permittivity Extraction, Applications, Open Challenges and Future Research Directions

“…Another important key restrict factor is the limited measurement applications based on microwave planar resonators. Most of the researchers focused on the liquid materials’ detection along with their binary mixtures or concentrations [ 82 , 95 , 118 , 133 , 134 , 135 , 136 ], while others focused on certain applications such as solid material detection [ 93 , 137 , 138 ], aqueous glucose detection [ 10 , 83 , 134 , 139 ] and food detection [ 74 ]. Therefore, there is the desire for novel sensors that could be applied in various measurement applications and offer an enhanced performance with lower production cost.…”

“…The transmission and reflection measurement techniques are considered in this comparison. Most of the researchers focused on liquid materials' detection along with their binary mixtures or concentrations [82,95,118,[133][134][135][136], while others focused on certain applications such as solid material detection [93,137,138], aqueous glucose detection [10,83,134,139] and food detection [74].…”

Microwave Planar Resonant Solutions for Glucose Concentration Sensing: A Systematic Review

“…More complex approaches combining a larger number of SRR have reported interesting sensitivity raises [41]. In order to increase the line capacitance of the sensor, interdigital capacitor gaps have been considered in different configurations for water-glucose measurements [30,124,125]. The use of complementary electric LC resonators has also been reported for microfluidic applications with aqueous and biological samples [108,126] (see Figure 3b).…”

MAS: Standalone Microwave Resonator to Assess Muscle Quality

“…Glucose sensing is an area in which a lot of different sensors have been developed [ 18 , 19 , 20 , 21 ]. Microwave sensors developed on flexible substrate materials are also researched with the added benefit of having a sensor that is conformal to the body and not a rigid structure [ 22 , 23 , 24 ]. Also, the feasibility of using the fat channel for intra-body communication at microwave frequencies has been studied [ 25 ].…”