A Single-Cell Impedance Micro-Cytometer Featuring 3D Electro-Fluidic Structures Monolithically Integrated Within Silver Pdms

摘要

This work for the first time demonstrates a single-cell impedance micro-cytometer with 3D differential electrodes and fluidic sidewalls completely made of silver-PDMS composites (AgPDMS). Such monolithically integrated electro-fluidic structure is an outcome of one-step molding from a readily used master, obviating extra sacrificial layer patterning as required in the existing device incorporating AgPDMS electrodes. To maintain maximum sensitivity, the device exploits 3D sidewall electrode configured differentially with minimized sensing volume between the electrodes. The micro-cytometer has been showcased here for flow impedance measurement of polystyrene microspheres at multiple frequencies, as well as real-time differentiation between 7 μm beads and human red blood cells (RBCs) featuring similar size.