Self-aligned sequential lateral field non-uniformities over channel depth for high throughput dielectrophoretic cell deflection

Dielectrophoresis (DEP) enables the separation of cells based on subtle subcellular phenotypic differences by controlling the frequency of the applied field. However, current electrode-based geometries extend over a limited depth of the sample channel, thereby reducing the throughput of the manipulated sample (sub-mu L min(-1) flow rates and <10(5) cells per mL). We present a flow through device with self-aligned sequential field non-uniformities extending laterally across the sample channel width (100 mu m) that are created by metal patterned over the entire depth (50 mu m) of the sample channel sidewall using a single lithography step. This enables single-cell streamlines to undergo progressive DEP deflection with minimal dependence on the cell starting position, its orientation versus the field and intercellular interactions. Phenotype-specific cell separation is validated (>mu L min(-1) flow and >10(6) cells per mL) using heterogeneous samples of healthy and glutaraldehyde-fixed red blood cells, with single-cell impedance cytometry showing that the DEP collected fractions are intact and exhibit electrical opacity differences consistent with their capacitance-based DEP crossover frequency. This geometry can address the vision of an all electric selective cell isolation and cytometry system for quantifying phenotypic heterogeneity of cellular systems.

Automated summary

This study introduces a novel method for cell separation using dielectrophoresis, which achieves efficient and precise separation by designing specific device geometries. Experimental validation on healthy and fixed red blood cells demonstrates the effectiveness of this method, highlighting its potential for further applications.