Development of a Microfluidic Device for Blood Cells Extraction in Liquid Biopsy

Abstract

This project aims to produce a microfluidic device capable of separating 6 μm and 20 μm diameters particles by inertial sorting. This Lab-on-Chip (LoC) was designed with a trapezoidal cross-section for better fluid control and effective particle manipulation at the microscopic level, as demonstrated by COMSOL simulations. The device was manufactured on a substrate of Polymethyl Methacrylate (PMMA) by femtosecond laser technology and then assembled using an innovative geometry-preserving Isopropyl alcohol-based procedure. The LoC was test with spherical plastic microparticles of two diameters (6 μm and 20 μm) suspended in distilled water. The separation efficiencies were (98.2 ± 1.6) % for 20 μm diameter particles and (70.0 ± 1.8) % for 6 μm diameter particles in good agreement with the simulation results. Finally, after a microfluidic channels’ acetone vapors treatment, the device demonstrated a good ability to separate biological particles (Red Blood Cells) at different concentrations (20%, 30%, 40%, 50%) in a PBS buffer.