STAN BIO - BILIRUBIN Flashcards
Most routine clinical procedures for the determination of serum bilirubin
are based on the ___
classical Diazo reaction of Ehrlich
classical Diazo reaction of Ehrlich which was first applied to the estimation of this bile pigment in serum in what year and who are the people involved
1913 by Van den Berg and Snapper
An excellent review of many bilirubin methodologies
is given by __
Winkelman and his co-workers
When a solution of ___ in____ is combined
with one of ____, _____ is formed.
sulfanilic acid + dilute hydrochloric acid
sodium nitrite
= nitrous acid
This unstable acid, which must be freshly prepared for each group of assays, react to form ___
diazotized sulfanilic acid
diazotized sulfanilic acid also known as
p-benzenediazonium sulfonate”
p-benzenediazonium sulfonate couples with bilirubin to produce __
azobilirubin
the color
intensity of which is proportional to __.
bilirubin concentration
Since bilirubin standards suffer from a high degree of instability, the method presented utilizes a aqueous solution of ___ as a calibrator,
N-1naphthylethylenediamine dihydrochloride
the N-1naphthylethylenediamine dihydrochloride as a calibrator is according or made by
Bilissis and Speer
The calibrator supplied has been
prepared to yield, for the technique described, a color equivalent to the
labelled bilirubin level at what wavelength.
540 nm
: Total Bilibubin reagent, Direct Bilirubin
reagent, oxidant, and calibrator are stable when stored at _____ until the
expiration date on their respective labels
15-30°C
Discard oxidant if a ___ develops.
dark yellow color
An eventual color change of
Total Bilirubin reagent may occur but this color will not interfere with the
assay.
true or false
true
Reportedly, about ____ of bilirubin can
be lost when exposed to sunlight for 1 hour
50%
Serum, or plasma collected by use of any of the common anticoagulants,
should be free of hemolysis and obtained in the fasting state to avoid
__ specimens
chylous
Bilirubin is stable in serum or plasma
____ at 2-8°C
and for
____ when frozen (-20°C).
4-7 days
3 months
: Gross hemolysis will cause falsely ___ bilirubin values, due to the inhibition of the diazo reaction by oxyhemoglobin
high
___ serum may cause a falsely elevated bilirubin values
Turbid or lipemic
Allow cuvettes to incubate at room temperature for exactly ___
3 minutes
formula
Total or Direct Bilirubin (mg/dL) = as-asb/ ak X 10
ref range
Total Bilirubin
Adults: 1.2
Newborns: 12.0
Direct Bilirubin
adults and Infants
(over 1 month) 0.5
