Dielectric properties characterization of saline solutions by near-field microwave microscopy

Abstract

Saline solutions are of a great interest when characterizations of biological fluids are targeted. In this work a near-field microwave microscope is proposed for the characterization of liquids. An interferometric technique is suggested to enhance measurement sensitivity and accuracy. The validation of the setup and the measurement technique is conducted through the characterization of a large range of saline concentrations (0–160 mg ml−1). Based on the measured resonance frequency shift and quality factor, the complex permittivity is successfully extracted as exhibited by the good agreement found when comparing the results to data obtained from Cole–Cole model. We demonstrate that the near field microwave microscope (NFMM) brings a great advantage by offering the possibility to select a resonance frequency and a quality factor for a given concentration level. This method provides a very effective way to largely enhance the measurement sensitivity in high loss materials.

Radio-Frequency Biosensors for Real-Time and Continuous Glucose Detection

“…Recently, the applicability of microwave for noninvasive and continuous glucose monitoring has led to the investigation of the dielectric properties of blood and other liquids as a function of glucose concentration. For this purpose, the dielectric properties of blood [ 45 ], blood plasma [ 43 ], saline solutions [ 46 ], and deionized water [ 47 ] have been presented recent decades. Additionally, samples with various glucose levels have been measured using diverse RF measurement systems, such as antennas and resonators, as summarized in Table 2 .…”

Intelligent Sensing Using Multiple Sensors for Material Characterization

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Microfluidic biochemical sensor based on circular SIW‐DMS approach for dielectric characterization application

“…As a result, the Q ‐factor and resonant frequency changes depending on the sample properties based on the resonant perturbation technique. Conventionally, several type of sensors employed to characterize the properties of material are such as dielectric, coaxial probe, and waveguide cavity resonator sensor . Their advantages include high Q ‐factors and sensitivity, hence resulting in higher measurement accuracy in wide range of applications.…”