Incorrect compensation beads for fixable viability dyes
Symptom
Fixable viability dyes (LIVE/DEAD, Zombie dyes) show no signal on standard antibody-capture beads or produce inconsistent compensation when using stained cells, causing spillover errors into viability channels.
Common Causes
1Amine-reactive viability dyes (NHS-ester based) do not bind antibody Fc regions on standard beads
2Using standard IgG-capture or species-specific beads instead of amine-reactive beads
3Biological cells provide inconsistent amine content varying by cell type and viability state
4Fixed cells have reduced or altered free amine availability compared to beads
Solutions
1Use amine-reactive compensation beads (7-7.9 µm) exclusively for all fixable viability dyes
2Stain amine-reactive beads with identical protocol used for cells (concentration, time, buffer)
3Never use standard antibody-capture beads or biological cells for viability dye compensation
4Essential for spectral cytometry where precise reference signatures are critical
5Include amine-reactive bead controls in every experiment using live/dead dyes