Dot blot

A dot blot (or slot blot) is a technique in molecular biology used to detect biomolecules, and for detecting, analyzing, and identifying proteins. It represents a simplification of the northern blot, Southern blot, or western blot methods. In a dot blot the biomolecules to be detected are not first separated by electrophoresis. Instead, a mixture containing the molecule to be detected is applied directly on a membrane as a dot, and then is spotted through circular templates directly onto the membrane or paper substrate. This differs from the western blot because protein samples are not separated electrophoretically. This is then followed by detection by either nucleotide probes (for a northern blot and southern blot) or antibodies (for a western blot).