Lanes 1 and 3 are 2 proteins protected by ProSieve ProTrack Dual Color Loading Buffer, while lanes
2 and 4 are proteins prepared and run in a standard loading buffer. Notice the severe degradation of proteins in these lanes.

ProSieve ProTrack blue dye allow you to follow the front of the protein separation in a PAGE gel, while the pink dye confirms full transfer of the proteins onto the blot.