A microfluidic integrated microliter millimeter wave biosensor based on a cell interception structure

Abstract The millimeter wave frequency band has the characteristics of high resolution, high sensitivity, label free, non-invasive [1], etc. Therefore, this detection technology has broad application prospects in the detection of microliter biological liquid samples. This article is based on the design of coplanar waveguides. A stepped interception structure is designed at the center of the microfluidic path of millimeter wave sensors to intercept and capture tumor cells entering the microfluidic path during fluid injection. This structure is used to improve the accuracy of detection by controlling the similar concentration of each cell. This broadband microfluidic sensor is used to measure the S parameters of different biological liquid samples, including tumor cell suspension HepG2 and THP-1 cell suspension (concentration 1E6 cells/mL), and data processing and error elimination are carried out using Matlab software. In the measurement results, the difference in transmission coefficients between different cell suspensions is aroun 0.4dB.