Bilirubin from Porcine Gall Bladder, 5g

Bilirubin is the principal pigment of bile and constituent of many biliary calculi and also found in blood. As the major end-product of the biological breakdown of heme, bilirubin is the chromophore responsible for coloration in various forms of jaundice. Bilirubin is suitable for use in the preparation of standard stock solutions of bilirubin for color density comparison in the determination of serum bilirubin. It appears to function as an antioxidant and efficient peroxyl radical scavenger, protecting membrane lipids from oxidation by these radicals. At nanomolar concentrations it has been shown to protect neurons from oxidative damage. Bilirubin is produced from Ox-gall which is sterilized before extraction with high pressure vapour at 120 °C. Then the bilirubin is extracted in a continuous extraction process with chloroform as a crude product. Recrystallization and purification is with ethanol and chloroform.