The highly abundant urinary metabolite urobilin interferes with the bicinchoninic acid assay


Autoria(s): Sampson, Dayle L.; Chng, Yee Lin; Upton, Zee; Hurst, Cameron P.; Parker, Anthony W.; Parker, Tony J.
Data(s)

01/11/2013

Resumo

Estimation of total protein concentration is an essential step in any protein- or peptide-centric analysis pipeline. This study demonstrates that urobilin, a breakdown product of heme and a major constituent of urine, interferes considerably with the bicinchoninic acid (BCA) assay. This interference is probably due to the propensity of urobilin to reduce cupric ions (Cu2+) to cuprous ions (Cu1+), thus mimicking the reduction of copper by proteins, which the assay was designed to do. In addition, it is demonstrated that the Bradford assay is more resistant to the influence of urobilin and other small molecules. As such, urobilin has a strong confounding effect on the estimate of total protein concentrations obtained by BCA assay and thus this assay should not be used for urinary protein quantification. It is recommended that the Bradford assay be used instead.

Identificador

http://eprints.qut.edu.au/66484/

Publicador

Elsevier Inc.

Relação

http://www.sciencedirect.com/science/article/pii/S000326971300345X

DOI:10.1016/j.ab.2013.07.027

Sampson, Dayle L., Chng, Yee Lin, Upton, Zee, Hurst, Cameron P., Parker, Anthony W., & Parker, Tony J. (2013) The highly abundant urinary metabolite urobilin interferes with the bicinchoninic acid assay. Analytical Biochemistry, 442(1), pp. 110-117.

Fonte

School of Biomedical Sciences; Faculty of Health; Institute of Health and Biomedical Innovation

Palavras-Chave #Urobilin; Bicinchoninic acid; Protein determination; Bile pigment; Bradford; Limits of agreement analysis
Tipo

Journal Article