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Bilirubin, Direct


  • Chemistry
  • Health Assessment and Safety

General Information

Name Information
A.K.A.:direct bilirubin
Matrix:Serum / Plasma
Application:Insurance Risk Assessment, Wellness
Turnaround Time:Daily
Analytical - Method:Acidified sodium nitrite produces nitrous acid, which reacts with sulfanilic acid (in acidic solution) to form a diazonium salt. The diazotized sulfanilic acid then reacts with bilirubin to form isomers of azobilirubin. In the direct bilirubin assay, only conjugated bilirubin is converted by the diazotized sulfanilic acid. The intensity of the red color of azobilirubin is measured photometrically and is proportional to the direct (conjugated) bilirubin concentration.
Units - Conventional:mg/dL

Specimen Information

Name Information
Minimum Volume:300 µL
Preferred Volume:500 µL
Rejection Criteria:

Improper labeling, improper sample handling, and wrong sample type.

Collection Instructions:

See “Blood Collection”

Collection Patient Preparation:NA
Container:Only the specimens listed below were tested and found acceptable. Serum: Collect serum using standard sampling tubes. Use non‑hemolyzed serum. Plasma: Use Li‑heparin plasma. Do not use other anticoagulants. Use non‑hemolyzed plasma.