Overview: [Characterization of red cell membrane proteins by SDS-PAGE] [research paper]
Topics: [gel analysis] [molecular mass standard curve] [measuring relative mobility] ["Hall of Shame"]
Data: [gel images]

Missing Dye Front Partial dye front – example 1 After doing so much work getting the gel set up, it is a shame to be late taking it down. Relative mobilities cannot be determined with accuracy if the dye front is partially off of the gel. In this case the gel was internally calibrated - that is, molecular weight standards were included on the gel. An arbitrary reference point can be used for setting up the standard curve, since the lanes were quite even. No dye front – example 2 This one was allowed to run until the dye front completely ran off. Since the lanes are somewhat distorted, relative mobility measurement will be compromised. With an intact dye front, lanes could be compared even if the gel was distorted or of different height on one side or the other. Relative migration is the same for a gel of uniform composition, no matter what the actual height of the resolving gel. No dye front – example 3 The curvature of this gel suggests that the spacers on the sides were a bit loose, causing a field effect near the edges (a 'frowning' gel). It will be difficult to get accurate relative mobility measurements because the dye front was allowed to run off. With an intact dye front as a reference point, lanes could be compared with one another despite the 'frown.'