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Updated: May 26, 2026

Immunoblot Analysis
16:01

Immunoblot Analysis

Published on: June 20, 2008

[An immunoblot technique]

T Imai1

  • 1Faculty of Science, Toho University.

After a protein is separated by various types of gel electrophoresis, it is transferred onto a nitrocellulose membrane, where a specified protein is detected through immunological reactions. This procedure, called an immunoblot technique, combines gel electrophoresis, which is capable of separating materials and immunological detection with specificity and high sensitivity. It has recently been used widely as a useful method for analyzing proteins in the fields of medicine, biochemistry, molecular biology and human genetics. The aim of this technique is to transfer a target protein, which is present in the gel, as efficiently as possible onto a membrane so that it can react uniquely on the membrane. To achieve this end, it is necessary to select the following; 1) a transfer system, 2) a transfer membrane, 3) a transfer buffer and additive, 4) optimal transfer conditions, and 5) a specific and highly sensitive means of immunological detection, to be combined with the technique. Since the immunoblot technique is, in principle, capable of analyzing all types of proteins as long as there is an antibody specific to the target protein, it can be used widely to determine the physiopathology of human proteins.

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