(113h) High-Throughput, Low-Loss Dielectrophoretic Cell Separation

Worldwide, the market for cell separation is dominated by three methods; fluorescence-activated cell sorting, magnetic-activated cell sorting, and density gradient methods; these variously suffer from drawbacks including high cell loss (typically >50%), the requirement for fluorescent or magnetic labels, and high cost (capital, operating or both). Dielectrophoresis was first used for cell separation over 50 years ago, and numerous systems for dielectrophoretically-activated cell sorting have been presented but few have matched existing methods for throughput and recovery. We have developed a cell enrichment system using the DEP-Well platform. Cells pass through 343 parallel wells containing 12 electrodes apiece, and energised by a 14Vpp signal at frequencies up to 1MHz. Processing speed is sufficiently high (in excess of 1 million cells per ml), and cell losses sufficiently low (below 5%), to enable multiple passes through the device in order to improve performance; on a second pass, separation efficiencies in excess of 95% are readily achievable; whilst on a third pass, recovery of rare cells becomes possible. Overall processing speed and recovery are comparable to or exceed FACS and MACS, whilst the use of a disposable chip avoids inter-separation contamination.