Low Event Rate During Acquisition

Symptom

Flow cytometer records very few events per second during sample acquisition, requiring extended run times to collect sufficient data. Analysis shows inadequate cell counts for statistically meaningful conclusions.

1. 1 Low cell concentration in sample (below 1x10^5 cells/mL), often due to cell loss during preparation, permeabilization, or fixation steps
2. 2 Cell clumps blocking tubing and preventing single-cell stream required for flow cytometry
3. 3 Excessive necrosis or apoptosis during sample preparation reducing viable cell numbers

1. 1 Adjust cell concentration to 1x10^6 cells/mL (optimal range 1x10^5 to 1x10^6); handle cells carefully during all preparation steps to minimize loss
2. 2 Mix sample gently immediately before running to dissociate clumps; filter cells through 30 μm nylon mesh in extreme cases to remove aggregates
3. 3 Keep wash buffers and reagents at 4°C during preparation to minimize necrosis and apoptosis; work quickly to reduce cell stress; ensure proper storage conditions

Related Video (3)

Bilibili (China-Accessible Mirrors) ★ 85

Flow Cytometry Experimental Operation in 7 Minutes

"Comprehensive hands-on flow cytometry protocol covering sample preparation and instrument operation—directly addresses the pre-acquisition steps where cell loss occurs"

Bilibili (China-Accessible Mirrors) ★ 82

Flow Cytometry Complete Workflow: Sample to Analysis

"Complete workflow from sample preparation through troubleshooting, explicitly covering the critical steps where low cell concentration develops before acquisition"

BioLegend ★ 78

Surface and Intracellular Cytokine Staining for Flow Cytometry

"Demonstrates fixation and permeabilization steps that are major causes of cell loss leading to low event rates during acquisition"