The band-sharpening effect relies on the fact that negatively charged glycinate ions (in the electrophoresis buffer) have a lower electrophoretic mobility than do the protein–SDS complexes, which, in turn, have lower mobility than the chloride ions (Cl − ) of the loading buffer and the stacking gel buffer.
[Cl−] > [protein–SDS] > [glycinate].
#Unit 13. Methods in Biology#Electrophoresis#Part B Pointers
