The AST is a cellular enzyme, is found in highest concentration in heart
muscle, the cells of the liver, the cells of the skeletal muscle and in smaller
amounts in other tissues.
Although an elevated level of AST in the serum is not specific of the
hepatic disease, is used mainly to diagnostic and to verify the course of
this disease with other enzymes like ALT and ALP.
Also it is used to control the patients after myocardial infarction, in skeletal
muscle disease and other 1,4,5.
Clinical diagnosis should not be made on a single test result; it should
integrate clinical and other laboratory data.
PRECAUTIONS
Contains sodium azide which can react with lead and copper plumbing, to
form potentially explosive azides. When disposing of such reagents, flush
with large volumes of water to prevent azide build up.
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.
- Thermostatic bath at 25ºC, 30ºC o 37ºC (± 0,1ºC)
- Matched cuvettes 1,0 cm light path.
- General laboratory equipment.
SAMPLES
Serum or plasma1: Stability 7 days at 2-8ºC.
INTERFERENCES
Anticoagulants currently in use like heparin, EDTA, oxalate and fluoride do not
affect the results. Haemolysis interferes with the assay1
A list of drugs and other interfering substances with AST determination has been
reported2,3.
