Molecular Separation Lab
Choose the gel. Set the field. Read the evidence.
Trial 1: Size the proteins in a mixture
Run Sample A beside the protein ladder, then identify the smallest protein.
SDS gives the proteins a similar negative charge-to-mass ratio. The polyacrylamide gel can now separate them mainly by size.
− Negative electrode (−)
Ladder
Sample A
Gel loadedChoose settings, predict the result, then run the gel.
Electric forceSmaller molecules move farther
+ Positive electrode (+)
Apparent mass (kDa)Wells and large molecules stay nearer the top