Southern blot

A Southern blot is a method used for the detection of a specific DNA sequence in DNA samples and can give information about DNA identity, size and concentration. Briefly, a DNA sample is cut with a restriction enzyme and separated on agarose gel  based on size. DNA fragments are transferred (blot)  to a nitrocellulose (or nylon) membrane. After hybridization with a specific probe and washing, the labeled DNA is visualized.