If this is not the case with the brand you use, add 1 drop of glycerol or a few grains of table sugar to weight the food color. The multi-colored mixture can serve as a standard or unknown for the experiment. Buffer may be flushed down the sink and gels discarded in the trash. Students may save the gels in plastic bags for later discussion, completion of analysis, or to share with parents. After 24 hours, the colors will remain vivid but the bands will no longer be discrete.
Safety Follow all guidelines for safe use of electrophoresis equipment.
When an electrical current is applied, the molecules will move through a gel. The direction and distance that the molecules migrate is related to the size and charge. Orient your gel with the wells on the left side. The top well is number 1. Complete the diagram above to assign colors and wells to each member of your group.