Visual determination of protein in urine using Bromochlorophenol Blue and a membrane filter

Citation
K. Yoshimoto et al., Visual determination of protein in urine using Bromochlorophenol Blue and a membrane filter, BUNSEKI KAG, 49(6), 2000, pp. 363-367
Citations number
12
Language
GIAPPONESE
art.tipo
Article
Categorie Soggetti
Spectroscopy /Instrumentation/Analytical Sciences
Journal title
BUNSEKI KAGAKU
ISSN journal
0525-1931 → ACNP
Volume
49
Issue
6
Year of publication
2000
Pages
363 - 367
Database
ISI
SICI code
0525-1931(200006)49:6<363:VDOPIU>2.0.ZU;2-X
Abstract
A visual method has been established for the determination of the urinary p rotein concentration with Bromochlorophenol Blue (BCPB) and a membrane filt er (MF). The acid-dissociation constant of HBCPB- is pK(a) (OH) = 4.2. At p H 3.0, ternary association occurs between HBCPB-, BCPB2- and protein in sol ution. After the associate is extracted onto a MF, HBCPB- in the associate undergoes a significant color change from yellow to blue upon drying. Free HBCPB- is not extracted onto a MF. The high extractability of the ternary a ssociate and the significant color change provide a sensitive visual method for protein detection. This method can be used to detect human serum album in in urine visually at concentrations as low as 40 mg/l. There was good ag reement between the results obtained for urinary protein by this method and those obtained by the conventional Coomassie Brilliant Blue spectrophotome try. The method reported here can be-used as a screening test for low, but increased, protein in urine.