Fig. 12. Illustrations of DEP in biological contexts. (A) In microfluidic chips, alternating current DEP is used to collect double-stranded λ-DNA molecules between aluminum electrodes. (B) Working principle of employing DEP in a ramping electric field to isolate HeLa cells.163 (C) Bacterial cells trapped and accumulated for detection. When an electric field is generated, S. typhimurium is injected into a microfluidic channel and trapped at the detection region by pDEP.164 (D) CTC enrichment technique principle. A DEP force is applied to the cells, and as a result of the non-uniformity of the electric field is exposed on the bottom surface of each microwell in this design.165.
