Rapid preparation and single-cell analysis of concentrated blood smears using a high-throughput blood cell separator and a microfabricated grid film.

Cytological examination of peripheral white blood cells inhomogeneously distributed on a blood smear is currently limited by the low abundance and random sampling of the target cells. To address the challenges, we present a new approach to prepare and analyze concentrated blood smears by rapidly enriching white blood cells up to 32-fold with 92% recovery on average at a high throughput (1mL/min) using a deterministic migration-based separator and by systematically analyzing a large number of the cells distributed over a blood slide using a microfabricated grid film. We anticipate that our approach will improve the clinical utility of blood smear tests, while offering the capability to detect rare cell populations.