Determination of Conjugated and Unconjugated Bilirubin by Methods Based on Direct Spectrophotometry and Chloroform-Extraction. A Reappraisal

Abstract

The direct spectrophotometry method (15) for determination of conjugated and unconjugated bilirubin is seriously sensitive to hemoglobin admixture. In samples without hemolysis both the direct spectrophotometry method and the chloroform-extraction method (16) include a bilirubin conjugate (most probably bilirubin monoglucuronide) in the unconjugated fraction. The effect of pH on the partition of this bilirubin conjugate between a water and a chloroform phase is studied.

Key Words:

• Bilirubin
• chloroform-extraction
• glucuronides
• hemolysis
• jaundice
• spectrophotometry