An X-ray film can detect both the radioactive and chemiluminescent signals from Western, Northern or Southern blot. It is placed against the blot membrane in a light-proof cassette. After the exposure for an appropriate time period, the film is developed by an auto-processor in a darkroom.
The northern blot is used to study gene expression by detection of RNA (or isolated mRNA). A general blotting procedure starts with the separation of RNA by electrophoresis. The RNA can then be transferred to a nylon membrane through a capillary system and detected with a hybridization probe.
The Southern blot is used to detect a specific DNA sequence in DNA samples. A general blotting procedure starts with the separation of digested DNA fragments. The DNA can then be transferred to a nylon membrane through a capillary system and detected with a hybridization probe.
Western Blotting is an analytical technique used to detect specific proteins in a given sample. It uses gel electrophoresis to separate native or denatured proteins by the length of the polypeptide. The proteins are then transferred to a membrane where they are detected using antibodies specific to the target protein.
Ponceau S is a rapid and reversible staining method for locating protein bands on Western blots producing reddish pink stained bands. The stain is useful because it does not appear to have a deleterious effect on the sequencing of blotted polypeptides and can be completely removed from the protein bands by continued washing.
Stripping is used to remove primary and secondary antibodies from a western blot membrane to allow the incubation of new antibodies. It is useful to save samples, materials, and time when you want to investigate more than one protein on the same blot.
There are several wash steps involved in western blot protocol. Abnova designed a western blot washer machine which can change the washing buffer automatically and shake by programs we setup.