Low OD Value for Zero Standard in Competitive ELISA

Symptom

The zero standard (B0, representing maximum antibody binding without competing analyte) produces lower than expected optical density values, reducing overall assay sensitivity and dynamic range.

1. 1 Insufficient capture or detector antibody concentration
2. 2 Inadequate substrate incubation time
3. 3 Antibody binding affinity compromised due to suboptimal storage
4. 4 Substrate reagent expired or improperly stored

1. 1 Optimize and increase antibody concentration through titration experiments
2. 2 Extend substrate incubation time to allow sufficient color development
3. 3 Verify antibody storage conditions and prepare fresh working solutions
4. 4 Check substrate expiration date and ensure proper storage at recommended temperature

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