Liver Function (Bilirubin Determination) Flashcards
Bilirubin determination specimen
Fasting Serum
Bilirubin Determination Specimen Requirements
Avoid Exposure to light
Avoid Hemolysis (false decreased)
Lipemia (falsely increased)
Exposure to light; decreases bilirubin ____ per hour
30-50%
Bilirubin Determination Principle
Van De Berg Reaction
diazotization of bilirubin to produce AZOBILIRUBIN
Van De Berg Reaction
Diazo Reagent consist of (2)
0.1% Sulfanilic acid + HCI
0.5% Sodium Nitrite
Reacts with diazo reagent with an accelerator
B1
Reacts with diazo reagent without accelerator
B2
Reaction with diazo reagent is same with B2
Delta Bilirubin
No coupling accelerator; determine DIRECT BILIRUBIN ONLY
Direct Method
With Accelerator; Determines both B1 and B2
Indirect Method
Indirect Method (2)
Evelyn Malloy
Jendrassik-Grof
Accelerator: 50% Methanol
Stopper: None
pH: acidic (1.2)
End color: Red-Purple
Absorbance: 560 nm
Evelyn Malloy
Accelerator: Caffeine benzoate
Stopper: Ascorbic acid
pH: Alkaline Tartrate/Sodium Acetate Buffer
End color: PINK-BLUE
Absorbance: 600 nm
Jendrassik-Grof
Determine Bilirubin concentration by measuring at 455 nm
This method is only used for measuring total Bilirubin
HDN
Direct Spectrophotometry
