Electrophoresis Time Not Optimized for Target Protein

Symptom

Protein bands do not align with expected molecular weight markers, with systematic upward or downward shifts affecting all bands uniformly. Pre-staining reveals migration issues before antibody detection.

1. 1 Running time and voltage combination not calibrated for specific gel composition and protein size range
2. 2 Manufacturer instructions followed without adjustment for specific target protein characteristics
3. 3 Lack of real-time monitoring of ladder marker separation during electrophoresis
4. 4 Running parameters optimized for different protein size range than target of interest

1. 1 Run gel at 100-150V for 1-2 hours as starting point, adjusting based on target protein molecular weight
2. 2 Frequently monitor ladder marker separation, stopping when target protein size range shows adequate resolution
3. 3 Use pre-chilled electrophoresis buffer to maintain consistent gel temperature during run
4. 4 Perform Coomassie blue staining of membrane after transfer to verify proper band positions before immunostaining
5. 5 Document optimal running times for specific protein targets to establish laboratory-specific protocols

Related Video (3)

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