Western blotting (protein immunoblotting) is an analytical technique used to identify and locate specific proteins in a sample of tissue homogenate or extract, based on their ability to bind to specific antibodies.

1. IMMUNOLOGY
Yash Gupta
Department of BiotechnologyEngineering
Institute of Engineering and Technology
Bundelkhand University, Jhansi

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3. It is based on the principle of immunochromatography where
proteins are separated according to their molecular weight into
polyacrylamide gel
The separated proteins are tagged by specific antibodies having
high affinity and specificity for the protein of interest
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4. Figure 1. Principle of westernblotting
(Source: https://www.elabscience.com/List-detail-306.html)
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6. Figure 2.Procedure of western blotting (Mahmood & Yang, 2012)
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7. Identification of specific protein in a complex mixture of proteins
Estimation of the size of the protein as well as the amount of the protein present
in the mixture
Demonstration of the specific antibodies in the serum for the diagnosis of
diseases
Can also be used for confirmative test for Hepatitis B infection
Used as definitive test for Bovine Spongiform Encephalopathy (BSE)
Used as confirmatory test for HIV
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8. Bass, J. J., Wilkinson, D. J., Rankin, D., Phillips, B.E., N. J., Smith, K., & Atherton,
P. J. (2017). An overview of technical considerations for Western blotting
applications to physiological research. Scandinavian Journal of Medicine
and Science inSports, 27(1),4–25.https://doi.org/10.1111/sms.12702
Mahmood, T.,& Yang, P. C. (2012). Western blot: Technique, theory, and
trouble shooting. North American Journal of Medical Sciences, 4(9),429–434.
https://doi.org/10.4103/1947-2714.100998
Eslami, A., & Lujan, J. (2010). Western blotting: sample preparation to
detection. J Vis Exp., 14(44),1-2.https://doi.org/10.3791/2359
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