What are the differences between Northern blot, Southern blot and Western blot?
Posted November 19, 2020
Answer
Blotting techniques are commonly used to identify and separate a target molecule from a complex mixture of molecules. While they all follow a similar type of workflow, each blotting technique differs in the type molecule it can identify. The following table outlines the differences between each blotting technique.
Technique | Western Blot | Northern Blot | Southern Blot |
Target Molecule | Protein | RNA | DNA |
Sample Prep | Protein extraction | RNA isolation | DNA extraction |
Separation | Gel Electrophoresis/SDS-PAGE | Gel Electrophoresis | Gel Electrophoresis |
Membrane Material | Nitrocellulose/PVDF | Nylon | Nylon |
Probe | Uses a single primary antibody or a combination of primary and secondary antibodies conjugated to either a fluorophore or enzyme | RNA, DNA or oligodeoxynucleotide | Nucleic acid probe |
Detection | Film, CCD camera, LED or infrared imaging system | X-Ray film, chemiluminescence | X-Ray film, chemiluminescence |
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