ABSTRACT
Separating proteins based on their molecular sizes and charges is possible because these factors determine how fast they travel through gels. In order to separate proteins from complex mixtures, sodium dodecyl-sulfate polyacrylamide gel electrophoresis (SDS-PAGE) is commonly used. Proteins bind strongly to SDS, with approximately one detergent molecule binding to two amino acids when SDS is present at 0.1%. Proteins gain a negative charge in proportion to their molecular size when boiled with SDS, and they, therefore, travel in the acrylamide gel in that order.
