On-chip flow cytometry using integrated photonics (Invited Paper)

The successful implementation of cell therapies in clinical practice poses the need to increase the throughput and automation of cell analysis and isolation techniques. Currently, the required level of throughput is difficult to reach with commercial, GMP-compliant cell sorters. A solution providing higher throughput can be provided by multichannel flow cytometers. We recently demonstrated for the first time a scalable, on-chip flow cytometer with monolithically integrated photonics and fluidics ​(Ref. 1)​. The device, fabricated using CMOS-compatible technologies, combines microfluidics and integrated photonics in different layers on the same substrate. As such, both the illumination of cells, and the collection of scattered light were realized using photonic integrated circuits in different layers of the stack. We demonstrate that the forward- and side-scattered light of white blood cells collected on-chip provides sufficient resolution for the detection and classification of the lymphocyte and monocyte subpopulations present in a full peripheral blood mononuclear cell sample.