AAT Bioquest

Why does the sample stream in flow cytometer need to be aligned in single file?

Posted June 22, 2020


The purpose of aligning the sample of cells or particles in single file is to increase the accuracy of the data by reducing the data spread. Without any focusing technique, the sample of cells or particles entering the flow cell would be moving in a random and disorganized manner, which may result in two possible consequences:

  • (1) Variability may be introduced in the data since cells are travelling at different speeds.
  • (2) Coincident events (two cells being analyzed at the same time instead of separately) may be collected because cells are in too close proximity to each other.
Additional resources

Fundamentals of Flow Cytometry

Cell Meter™ FITC-Annexin V Binding Apoptosis Assay Kit *Optimized for Flow Cytometry*

Picot, J., Guerin, C. L., Le Van Kim, C., & Boulanger, C. M. (2012). Flow cytometry: retrospective, fundamentals and recent instrumentation. Cytotechnology, 64(2), 109-130.

Nolan, J. P., & Condello, D. (2013). Spectral flow cytometry. Current protocols in cytometry, 63(1), 1-27.