Total And Direct Bilirubin Flashcards
Most routine clinical procedures for the determination of serum bilirubin are based on
Classical diazo reaction of ehrlich
first applied to the estimation of this bile pigment in serum in 1913 by
Van den berg and snapper
An excellent review of many bilinubin methodologies is given by
Winkelman and his co-worker
solution of bilirubin
Sulfanilic acid in dilute hydrochloric acid combined with sodium nitrate
When a solution of sulfanilic acid in dilute hydrochloric acid is combined with one of sodium nitrite it formed
Nitrous acid
The latter also termed
P-benzenediazonium sulfonate
The latter (also termed “p-benzenediazonium sulfonate*) couples with bilirubin to produce
Azobilirubin
The method utilized aqueous solution as calibrator
N-1-napthylethylenediamine Dihydrochloride
The method utilized aqueous solution of N-1-napthylethylenediamaine dihydrochloride as calibrator according to
Bilissis and speer
color quivalent to the labelled bilirubin level at
540nm
Total bilirubin reagent
Sulfanilic acid in dilute hydrochloric acid
Direct bilirubin reagent
Sulfanilic acid in dilute hydrochloric acid
Bilirubin oxidants
Sodium nitrate
Bilirubin calibrator
N-1-napthylethylenediamine-dihydrochloride
Total Bilibubin reagent, oxidant and calibrators are
stable
when stored at
15-30C
Discard oxidant if a ___________ color develop
Dark yellow
Specimen of choice
Serum or plasma (use of any common anticoagulant)
should be free of hemolysis because
It can result falsely decrease
bilirubin is highly __________.
photolabile
Avoid lipemic because
It can cause falsely increase
Light 30-50% be lost when expose to 1hr because
It can falsely decrease
Bilirubin is stable in serum or plasma: 4-7 days
2-8C
Bilirubin is stable in serum or plasma: 3months
20C (frozen)
Cross hemolysis will cause falsely low bilirubin values, due to
inhibition of the diazo reaction by oxyhemoglo-
bin
Total bilirubin reagent (ml/ul)
1.0mL (1000ul)
Total bilirubin oxidant how many drop
1 drop
Total bilirubin calibrator (ml/ul)
0.05ml (50uL)
Total bilirubin sample (ml or ul)
0.05ml (50ul)
Total bilirubin h2o (ml/ul)
0.05ml (50ul)
Total bilirubin incubation
Room temp (5mins)
Total bilirubin read at
540nm
Total bilirubin calculations
Abs of unknown/ abs of std x 10 mg/dl
Total bilirubin normal value
1.2 mg/dl
Direct bilirubin reagent (ml/ul)
1.0ml (1000ul)
Direct bilirubin oxidant how many drops
1 drop
Direct bilirubin calibrator (ml/ul)
0.1ml (100ul)
Direct bilirubin sample (ml/ul)
0.1ml (100ul)
Direct bilirubin h2o (ml/ul)
0.1ml (100ul)
Direct bilirubin incubation at
3mins only
Read Direct bilirubin
540nm
Direct bilirubin calculation
Abs of sample-abs of sb /abs of K x 10mg/dl
Direct bilirubin calculation
Abs of samp-abs of sb/ abs of K x 10mg/dl
For newborns, usually only __________ is requested.
total bilirubin
Total bilirubin normal value for infant
12.0mg/dl
Direct bilirubin normal value
0.5 mg/dl
