Split Ring Resonator Sensor Designed for Complex Permittivity Measurement of Tiny Biological Materials

This paper presents a novel microfluidic split ring resonator (SRR) with the planar structure to identify and analyze the complex permittivity of tiny biological materials. The sensor is designed based on the resonant perturbation method which has high optimum and precision sensitivity. The structure device is implemented by using a split ring topology at 5.5 GHz with micro-volume (µL) biological samples. The split-ring excitation demonstrates significant changes in resonant frequency and Q factor when samples was involved, which can be used to the measurement of complex permittivity of biological materials and single cell.