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Western Blot (Sigma Protocol) minor

Black Spots on Membrane

Symptom
Random black spots or speckles appear on the western blot membrane
Common Causes
  1. 1 Blocking reagent has clumped and antibodies are binding to aggregates
  2. 2 Contaminating enzymes present in sample or blocking buffer
Solutions
  1. 1 Filter the blocking reagent before use
  2. 2 Filter the blocking buffer to remove particulates
Related Video (2)
Cell Signaling Technology ★ 85
Western Blot Troubleshooting Guide
"Directly addresses western blot troubleshooting, likely covering black spots from antibody aggregates."
Bilibili (China-Accessible Mirrors) ★ 70
Reliable and Reproducible Western Blot Results
"Focuses on reproducible methodology that could help prevent blocking reagent clumping and antibody aggregation."
Source: sigmaaldrich.com ↗
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