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ELISA Development severe

Excessive Signal - Entire Plate Turned Blue

Symptom
Whole plate turned uniformly blue indicating non-specific signal saturation
Common Causes
  1. 1 Insufficient washing or skipped washing step leaving unbound peroxidase
  2. 2 Substrate solution mixed too early and turned blue prematurely
  3. 3 Excessive streptavidin-HRP concentration
  4. 4 Reused plate sealers or reagent reservoirs with residual HRP
  5. 5 Buffers contaminated with metals or HRP
Solutions
  1. 1 Follow proper washing procedure from ELISA Development Guide page 4
  2. 2 Mix and use substrate solution immediately before use
  3. 3 Check streptavidin-HRP dilution and titrate if necessary
  4. 4 Use fresh plate sealer and reagent reservoir for each step
  5. 5 Make fresh buffers
Related Video (3)
Thermo Fisher Scientific ★ 85
How to Run an ELISA Assay – Invitrogen Kit Step-by-Step Tutorial
"Direct, step-by-step ELISA protocol showing correct washing steps to avoid non-specific signal."
Bilibili (China-Accessible Mirrors) ★ 80
DuoSet ELISA — Sandwich ELISA Hands-on Protocol (Bio-Techne)
"Hands-on sandwich ELISA protocol includes substrate development and washing to prevent plate-wide color."
Thermo Fisher Scientific ★ 70
How to coat your own plate and run an Invitrogen ELISA kit
"Shows coating and running an ELISA kit, relevant for understanding assay steps where washing is critical."
Source: rndsystems.com ↗
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