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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 (2)
YouTube (Curated Tutorials) ★ 85
A Guide to the Colony Forming Cell Assay: Methods and Tips
"Explicitly addresses consistency and optimization tips throughout the protocol, directly targeting the seeding consistency problem identified as the root cause."
Bilibili (China-Accessible Mirrors) ★ 82
Colony Formation Assay — Step-by-Step Protocol (Bio-Techne)
"Covers seeding density optimization as a key step, which is the critical control point for preventing replicate variation in colony formation assays."
Source: xiaohongshu.com ↗
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