What is the function of a western blot?

The function of a western blot is to identify specific proteins within a sample using antibody binding. This technique involves several critical steps: first, proteins are separated based on their size through gel electrophoresis. After separation, the proteins are transferred onto a membrane, where they are immobilized. The next step involves incubating the membrane with specific antibodies that bind to the target proteins. By detecting these antibodies, which are usually linked to a reporter enzyme or a fluorescent tag, researchers can visualize and quantify the proteins of interest. This powerful method allows scientists to study protein expression levels and post-translational modifications, making it an essential tool in biochemistry and molecular biology.

The other choices describe different laboratory techniques. Amplifying DNA sequences pertains to PCR (Polymerase Chain Reaction), separating small molecules usually refers to chromatography techniques, and visualizing RNA sequences relates to methods like Northern blotting or RNA sequencing. They do not function in the same way as a western blot, which is specifically focused on proteins.