Determination of Protein Concentration: Spectrophotometry

"There are several ways of estimating the protein concentration such as amino acid analysis following acid hydrolysis of the protein; analyzing the changes in the spectral properties of certain dyes in the presence of proteins; and spectrophotometric estimation of the proteins in near or far UV region. Although dye-binding assays and amino acid analysis following acid hydrolysis of the protein can be used for estimating the protein concentration for both pure as well as an unknown mixture of proteins; UV spectroscopic quantitation holds good for the pure proteins. If a protein is pure, UV spectroscopic quantitation is the method of choice because it is easy and less time consuming to perform; furthermore, the protein sample can be recovered back".

One of the biggest obstacles as an overall whole, was the calculation part of the experiment, I have attached a video that helps better explains the process of finding the standard curve. 



REFERENCES

[1] Scopes, R. K. (1974) Measurement of protein by spectrometry at 205 nm. Analytical Biochemistry, 59, 277–282. 

[2] Waddell, W. J. (1956) A simple UV spectrophotometric method for the determination of protein. The Journal of Laboratory and Clinical Medicine,48, 311–314.

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