Final answer:
SDS-PAGE separates proteins based on size, whereas Western Blotting uses antibodies to identify specific proteins after they have been separated by SDS-PAGE.
Step-by-step explanation:
SDS-PAGE is good for determining protein size while Western Blotting is good to determine protein identity. SDS-PAGE, or sodium dodecyl sulfate polyacrylamide gel electrophoresis, separates proteins based on their molecular weight. Proteins are denatured with SDS, which imparts a uniform negative charge, allowing for separation purely by size when an electric field is applied.
In contrast, Western blotting, also known as immunoblotting, follows the separation of proteins by SDS-PAGE with the additional step of transferring proteins to a membrane and using antibodies to identify specific proteins. The process involves the use of primary antibodies that bind to the protein of interest, followed by secondary antibodies with an attached molecular beacon, facilitating the detection of the protein through either colorimetric or fluorescence signals.