How do you determine the molecular weight of proteins band by polyacrylamide gel electrophoresis?

To determine the molecular weight of proteins separated by polyacrylamide gel electrophoresis (PAGE), a standard curve is created using known molecular weight standards run alongside the samples. After electrophoresis, the bands of the proteins are visualized and their migration distances are measured. By plotting the log of the molecular weights of the standards against their respective migration distances, you can interpolate the molecular weight of your unknown protein based on its migration distance. This method relies on the principle that smaller proteins migrate further through the gel compared to larger ones.