Flow cytometry SSC channel shows elevated background noise from small particles and debris. Event plots display excessive scatter in low SSC/FSC regions, indicating presence of cell fragments or contaminants.
Common Causes
1Cell lysis due to non-fresh samples or improper preparation protocols, creating membrane fragments
2High centrifuge rotor speed or excessive vortexing causing mechanical cell damage and fragmentation
3Bacterial contamination in sample producing autofluorescence at low level and high event rates
Solutions
1Ensure cells in sample have not lysed; use fresh samples and proper preparation techniques
2Do not centrifuge cells at high rotor speed (keep below 300-400 x g); avoid violent vortexing; handle cells gently throughout protocol
3Ensure sample is not contaminated; work in sterile conditions; use aseptic technique during cell preparation; filter samples if necessary