The term "Western blot" refers to a laboratory technique used in molecular biology and biochemistry to detect and analyze specific proteins in a sample. Developed in the late 1970s, Western blotting is a method that involves the separation of proteins by size, their transfer to a membrane, and subsequent detection using specific antibodies.
Western blotting begins with the separation of proteins in a sample using gel electrophoresis. The proteins are subjected to an electric field, causing them to migrate through a gel matrix based on their size. After separation, the proteins are transferred to a solid support, such as a nitrocellulose or polyvinylidene fluoride (PVDF) membrane. This process, known as blotting, allows for the immobilization of proteins on the membrane.
Once the proteins are immobilized on the membrane, they can be probed with specific antibodies to detect the target protein of interest. Antibodies bind to their specific protein targets, enabling their detection using various methods, such as chemiluminescence or fluorescence. By comparing the band intensities between different samples, researchers can analyze protein expression levels or detect the presence of specific proteins.
The term "Western" in "Western blot" is believed to have been derived from its counterpart technique, named "Southern blotting," which was used to analyze DNA samples. Western blotting has become a fundamental tool in molecular biology and is widely used in research, diagnostics, and pharmaceutical development to study protein expression, identify biomarkers, and understand disease mechanisms.
