Urea is the final result of the metabolism of proteins; It is formed in the
liver from their destruction.
It can appear the urea elevated in blood (uremia) in: diets with excess
of proteins, renal diseases, heart failure, gastrointestinal hemorrhage,
dehydration or renal obstruction1,4,5.
Clinical diagnosis should not be made on a single test result; it should
integrate clinical and other laboratory data.

STORAGE AND STABILITY

All the components of the kit are stable until the expiration date on the
label when stored tightly closed at 2-8ºC, protected from light and
contaminations prevented during their use.
Do not use reagents over the expiration date.
Signs of reagent deterioration:
– Presence of particles and turbidity.
– Blank absorbance (A) at 340 nm 1,00.

ADDITIONAL EQUIPMENT

– Spectrophotometer or colorimeter measuring at 340 nm.
– Matched cuvettes 1,0 cm light path.
– General laboratory equipment (Note 2).

SAMPLES

– Serum or heparinized plasma1
: Do not use ammonium salts or
fluoride as anticoagulants.
– Urine1
: Dilute sample 1/50 in distilled water. Mix. Multiply the
results by 50 (dilution factor). Preserve urine samples at pH 4.
Urea is stable at 2-8ºC for 5 days.