Solvent-Based Optimization of CSRR and IDC RF Bio-Sensors

Abstract

Complementary Split Ring Resonators (CSRR) and Inter-Digitated Capacitors (IDC) based RF sensors have been ubiquitously optimized assuming empty cavities. However, in bio-sensing applications, most of the samples are dissolved in respective solvents. As a result, designing sensors based on specific solvent-filled cavities is the optimal approach for future RF bio-sensors. This paper presents the application of Binary Particle Swarm Optimization (BPSO) technique for maximizing the sensitivity of CSRR and IDC sensors. BPSO optimizes the designs by cell patterning the sensing region in the presence of phosphate buffer as a solvent. An enhancement of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$47.38\times $ </tex-math></inline-formula> for the CSRR and <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$2.03\times $ </tex-math></inline-formula> for the IDC in the detection of L-Lysine at frequencies 2.18 GHz and 0.72 GHz respectively has been achieved, when compared to sensitivities of their traditional counterparts. Promising results have also been observed in the detection of sucrose and glucose, making it a suitable contender for optimization of next-generation RF bio-sensors.