Molar absorptivities of bilirubin (NIST SRM 916a) and its neutral and alkaline azopigments
Open Access
- 1 September 1990
- journal article
- research article
- Published by Oxford University Press (OUP) in Clinical Chemistry
- Vol. 36 (9) , 1698-1701
- https://doi.org/10.1093/clinchem/36.9.1698
Abstract
Three laboratories in the U.S. and two in the Netherlands determined molar absorptivities (epsilon) of Standard Reference Material (SRM) 916a Bilirubin from the National Institute of Standards and Technology. In caffeine reagent the average epsilon values were 50,060 and 48, 980 L.mol-1.cm-1 at 432 and 457 nm, respectively. The epsilon value of the blue azopigment, obtained with the Reference Method for total serum bilirubin, was 76,490 L.mol-1.cm-1 at 598 nm. When the addition of alkaline tartrate was omitted, the molar absorptivity of the red azopigment was 56,600 L.mol-1.cm-1 at 530 nm.This publication has 6 references indexed in Scilit:
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