Protocol Online logo
Top : New Forum Archives (2009-): : Biochemistry

dna loading dye for proteins - (Jun/07/2010 )

After loading our protein samples on to sds page we realized that we have added DNA loading dye instead of protein loading dye. I know that the difference in my dyes is for proteins i have a tris buffer and also a reducing agent, and sds for imparting uniform negative charge. What are the consequences of my protein resolution in this senario....

Thanks in advance


The SDS binds the proteins and renders them negatively charged, as you said. Thus, all proteins that have will be positively charged at the pH of your buffer (depends on the proteins Isoelectric Point) will not be pulled in the direction of the gel, but to the opening of the pocket. Also, as the charge/mass ratio is not the same for all proteins, you will not separate based on size...
You should, if possible repeat the experiment, as the position of your bands basically won't tell you much.


SDS is also one component of electrophoresis buffer, so slowly slowly the SDS bind to the protein and be pulled down with eletronic force. but no band can be formed since the protein is not running simultaneous .