Title: protein quantification
Long Title: IUPAC Gold Book - protein quantification
DOI: 10.1351/goldbook.09771
Status: current

Definition
Analytical methods and related techniques to measure the protein content.

Notes
1) Protein quantification can be further divided into relative quantification and absolute quantification. Basic analytical methods used in proteomics to quantify protein content are immunoanalysis (see Western blotting), mass spectrometry or densitometry of differential staining. Especially mass spectrometry offers many techniques based either on stable isotope labelling or label-free approaches.
2) Absolute quantification of proteins (AQUA) is performed via measurements on constituent proteolytic peptides using chemically synthesised isotope-labelled peptides as surrogate internal standards for mass spectrometry.

Related Term
- Western blotting: https://goldbook.iupac.org//terms/view/09789

Source
- PAC, 2018, 90, 1121. 'Terminology of bioanalytical methods (IUPAC Recommendations 2018)' on page 1161 (https://doi.org/10.1515/pac-2016-1120)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/09771/html
- json: https://goldbook.iupac.org/terms/view/09771/json
- xml: https://goldbook.iupac.org/terms/view/09771/xml

Citation: Citation: 'protein quantification' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.09771
License: The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) for individual terms.
Collection: If you are interested in licensing the Gold Book for commercial use, please contact the IUPAC Executive Director at executivedirector@iupac.org .
Disclaimer: The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using.
Accessed: 2026-04-18T03:51:28+00:00