Automatic Microfluidic Cell Wash Platform for Purifying Cells in Suspension: Puriogen

Cell wash is an essential cell sample preparation procedure to eliminate or minimize interfering substances for various subsequent cell analyses. The commonly used cell wash method is centrifugation which separates cells from other biomolecules in a solution with manual pipetting and has many drawbacks such as being labor-intensive and time-consuming with substantial cell loss and cell clumping. To overcome these issues, a centrifuge-free and automatic cell wash platform for cell purity generation, termed Puriogen, has been developed in this work. Compared with other developed products such as AcouWash, Puriogen can process samples with a high throughput of above 500 μL/min. Puriogen utilizes a uniquely designed inertial microfluidic device to complete the automatic cell wash procedure. One single-cell wash procedure with the Puriogen platform can remove more than 90% ambient proteins and nucleic acids from the cell sample. It can also remove most of the residual fluorescent dye after cell staining to significantly reduce the background signals for subsequent cell analysis. By removing the dead cell debris, it can increase the live cell percentage in the sample by 2-fold. Moreover, the percentage of single-cell population is also increased by 20% because of further disassociation of small-cell aggregates (e.g., doublets and triplets) into singlets. To freely adjust cell concentrations, the Puriogen platform can concentrate cells 5 times in a single flow-through process. The presented Puriogen cell wash solution has broad applications in cell preparation with its excellent simplicity in operation and wash efficiency, especially in single-cell sequencing.