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Research Article

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Pooya Afaghi
Michael Anthony Lapolla
Khashayar Ghandicorresponding author


There is a lack of fast and inexpensive analysis methods to study the conformational changes and the degree of denaturation of proteins quantitatively. As such, a novel analytical technique is developed based on the ultraviolet-visible (UV-Vis) absorption spectrum of proteins, and a mathematical modeling of the results. The phenomenon behind this technique is the shift of the absorption peak of amino acid residues of BSA such as tyrosine, phenylalanine, and tryptophan as the protein unfolds and these residues are exposed to the solvent. However, the portion of the peak that is shifted is miniscule and it can be enhanced by using the proposed technique in this paper. As an example, we also show how this technique was applied for evaluating the temperature effects on thermal denaturation of bovine serum albumin (BSA) protein. A degree of denaturation curve as a function of time was obtained at three different temperatures using this technique. The results are reproducible and consistent with those reported in the literature. This technique is especially recommended for analyses where several tests are needed quickly, and the amount of sample is limited. Among the applications, it can be used for evaluation of disinfection through assessing the degree of denaturation for pathogens proteins.

UV-vis spectroscopy, protein denaturation, bovine serum albumin, tyrosine, phenylalanine, tryptophan

Article Details

Supporting Agencies
This work was supported by Department of National Defence of Canada through the Innovation for Defence Excellence and Security (IDEaS) program.
How to Cite
Afaghi, P., Lapolla, M., & Ghandi, K. (2021). Determining the degree of denaturation of bovine serum albumin using a new UV analysis technique. Chemical Reports, 3(1), 173-176.


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