Single-cell microfluidic impedance cytometry: a review

Lab-on-chip technologies are being developed for multiplexed single cell assays. Impedance offers a simple non-invasive method for counting, identifying and monitoring cellular function. A number of different microfluidic devices for single cell impedance have been developed. These have potential applications ranging from simple cell counting and label-free identification of different cell types or detecting changes in cell morphology after invasion by parasites. Devices have also been developed that trap single cells and continuously record impedance data. This technology has applications in basic research, diagnostics, or non-invasively probing cell function at the single-cell level. This review will describe the underlying principles of impedance analysis of particles. It then describes the state-of-the-art in the field of microfluidic impedance flow cytometry. Finally, future directions and challenges are discussed.