Changes

 

Also known as immunoblotting, the Western blot technique is used to identify specific proteins or antibodies in complex mixtures and has largely overtaken the use of immunoelectrophoresis in research and diagnosis.

Also known as immunoblotting, the Western blot technique is used to identify specific proteins or antibodies in complex mixtures and has largely overtaken the use of immunoelectrophoresis in research and diagnosis.

===Principle===

==Principle==

In the Western blot technique, a protein mixture is electrophoretically separated onto a denaturing gel, separating the proteins according to molecular weight. The bands can then be identified by applying enzyme-/radio-labeled antibodies to the mixture and the resulting complexes visualised either by ELISA technique or autoradiography.  

In the Western blot technique, a protein mixture is electrophoretically separated onto a denaturing gel, separating the proteins according to molecular weight. The bands can then be identified by applying enzyme-/radio-labeled antibodies to the mixture and the resulting complexes visualised either by ELISA technique or autoradiography.  

===Method===

==Method==

# Protein mixture is treated with sodium dodecyl sulfate (SDS), a strong dissociating agent

# Protein mixture is treated with sodium dodecyl sulfate (SDS), a strong dissociating agent

# Mixture is separated by electrophoresis - takes place in SDS polyacrylamide gel (SDS-PAGE)

# Mixture is separated by electrophoresis - takes place in SDS polyacrylamide gel (SDS-PAGE)

# An ELISA reaction is used to detect the position of the antibodies

# An ELISA reaction is used to detect the position of the antibodies

===Applications===

==Applications==

*'''HIV testing'''- this is the most widely used application of this test, used to determine whether a patient is producing antibodies specific to viral proteins present during an HIV infection

*'''HIV testing'''- this is the most widely used application of this test, used to determine whether a patient is producing antibodies specific to viral proteins present during an HIV infection

[[Category:Immunological Testing]]

[[Category:Immunological Testing]]