Flow Cytometry (Fixation & Permeabilization) severe
Lack of Antibody-Specific Protocol Validation
Symptom
Inconsistent or failed staining when applying generic fixation/permeabilization protocols to different antibodies, especially transcription factors. Expected positive populations are negative or dim.
Common Causes
1Different antibodies require specific fixation and permeabilization conditions
2Transcription factors particularly sensitive to fixation/permeabilization protocols
3Epitope accessibility varies with different processing methods
4Vendor-recommended conditions not followed for specific antibody clones
Solutions
1Validate the protocol for each antibody, especially transcription factors
2Consult antibody datasheet for recommended fixation/permeabilization methods
3Perform titration experiments with different processing conditions for new antibodies
4Optimize fixation time and concentration separately for each critical target