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

Abstract

This work proposes an advancement of microwave planar resonator sensor with high sensitivity for microfluidic dielectric characterization. The physical design was employed based on circular substrate integrated waveguide (CSIW) with an integration of defected microstrip structure (DMS). This approach can be applied to accelerate the dielectric detection, structure miniaturization and material differentiation. The presented sensor operates based on variations in the dielectric properties of solvents in the vicinity of a planar open‐ended microstrip resonator device. Further analysis in volume and concentration were performed to validate the reliability of the sensor. Validation and functionality of the sensor were investigated by experimental and results comparison. A mathematical model was developed to determine the dielectric constant and the loss tangent of the microfluidic samples. The average error detection has a lower percentage value of 0.11% by comparison to the commercial and ideal dielectric properties of the aqueous samples. The maximum relative error detection, ±0.37% implied better accuracy compared to the existing resonator sensors with more than 400 of the Q‐factor. The proposed CSIW‐DMS sensor was found to give higher accuracy and detection response; besides easier to fabricate, and compatible for integration with other electronic components in an RF sensor for variety of applications.

Ultrafast Detection and Discrimination of Methanol Gas Using a Polyindole-Embedded Substrate Integrated Waveguide Microwave Sensor

“…Equations and indicate that the resonating frequency shift and Q factor variation are influenced by the real and imaginary permittivity of the sensing material, respectively. The dielectric characterization of the sensing material is worked in two steps: first, the resonating frequency shift occurs due to the changes in sensing material’s dielectric constant (ε′) via electric field perturbation, and second, the Q factor alteration arises due to the variation of sensing material’s dielectric loss (ε″) induced by the loss reaction in the electric field . Moreover, the effective permittivity of the sensing region is altered in two steps.…”

Permittivity measurement of fluidics with high‐sensitivity by chandelier form microwave sensor

“…The examples identified by the permittivity determination method include blood glucose, [21][22][23] moisture, [24][25][26][27] milk, 28 oil in food, 29 solution of sugar and salt, 30 amount of nitrate and phosphate. 31 The cavity technique is a method for researchers in the petroleum industry, therefore, the used MRSs in the industry can be fabricated by cavity model [32][33][34] or the amount of fat and impurities in types of milk was detected by the substrate-integrated waveguide structure. 35,36 Serialization of several MRS increases sensitivity.…”

Effective and low‐cost fluid concentration sensing biosensor based on step‐impedance resonators

“…Recently, liquid antenna technology is widely studied by researchers in the field of wireless communication, due to its advantages such as low‐power consumption, easy to manufacture, conformal, and achieve reconfigurable performances 1‐7 . Based on this, many innovative applications have been developed and promoted, such as integration of radio frequency technology with biological testing, chemical analysis, material characterization, 8,9 and so on. The microfluidic biosensor based on RF theory is one of the excellent applications.…”