Smile Effect on Western Blot Bands

Symptom

Bands appear curved in a smile-shaped pattern across the gel, with edges migrating faster than the center. This distortion affects all lanes uniformly and compromises molecular weight estimation.

1. 1 Voltage too high during electrophoresis causing excessively rapid migration
2. 2 Gel temperature too high during migration altering buffer pH
3. 3 Insufficient cooling during electrophoresis run
4. 4 Heat accumulation in center of gel due to lack of temperature control

1. 1 Decrease voltage according to protocol recommendations and gel specifications
2. 2 Run electrophoresis at 4°C on ice or in cold room
3. 3 Pre-chill running buffer before use
4. 4 For large proteins (>100 kDa), run overnight at constant low amperage and reduced voltage

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