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Colony Formation Assay severe

Replicate dishes vary widely — conclusion is unsupported

Symptom
Three replicates of the same group give very different colony counts. Showing only a representative image without statistics is misleading.
Common Causes
  1. 1 Seeding consistency was poor between dishes
  2. 2 Cell suspension was not well mixed before plating
  3. 3 Different operator handling between replicates
  4. 4 Failed to randomize plating order
Solutions
  1. 1 Always plate at least 3 replicates per condition
  2. 2 Pipette suspension thoroughly before each well to keep cells dispersed
  3. 3 Standardize the operator and protocol for every replicate
  4. 4 Report mean ± SD and the actual statistical test (t-test / ANOVA), not just a representative image
Related Video (3)
YouTube (Curated Tutorials) ★ 88
A Guide to the Colony Forming Cell Assay: Methods and Tips
"Step-by-step CFC protocol with optimization tips directly addresses consistent seeding, the root cause of variable replicate counts."
Bilibili (China-Accessible Mirrors) ★ 82
Colony Formation Assay — Step-by-Step Protocol (Bio-Techne)
"Protocol explicitly covers seeding density optimization and colony counting, targeting the seeding-consistency failure and the counting/quantification gap."
YouTube (Curated Tutorials) ★ 60
Clonogenic Cell Survival Assay (Colony Formation Assay)
"Covers clonogenic assay fundamentals and analysis, moderately useful for understanding context though less focused on seeding consistency."
Source: xiaohongshu.com ↗
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