White stripes on SDS-PAGE gels may be caused by:

These steps can fix the issue..

Try running the gel at constant current (50 mA) instead of voltage, due to the difference in voltage sometimes cause this issue. And wash out the tracking dye through gel after it reaches the bottom. Hope it helps.

1. Incomplete Polymerization of the Gel:

• Cause: If the acrylamide gel did not polymerize properly, it can create a cloudy or uneven appearance.
• Solution:Use freshly prepared APS and TEMED to ensure proper polymerization. Allow sufficient time for the gel to set (typically 30–60 minutes). Check the ratio of acrylamide to bis-acrylamide and ensure it's appropriate for a 12% gel.

2. Residual Gel Components:

• Cause: Unreacted acrylamide or bis-acrylamide can create a white or cloudy appearance after staining.
• Solution:Wash the gel thoroughly with distilled water before staining. Ensure complete washing after the staining and destaining steps to remove excess dye.

3. Staining and Destaining Artifacts:

• Cause: Overstaining with Coomassie Blue or inadequate destaining can result in uneven or cloudy background.
• Solution:Optimize the staining protocol by reducing staining time (e.g., 1 hour instead of overnight). Destain the gel thoroughly with 30–40% methanol and 10% acetic acid, changing the solution multiple times until the background is clear.

4. SDS Precipitation:

• Cause: SDS can precipitate during electrophoresis or staining, leading to a white appearance.
• Solution:Ensure the running buffer and sample buffer contain fresh SDS at the correct concentration (e.g., 0.1%–0.2%). Avoid running the gel at too low a temperature, as this can cause SDS precipitation.