Clinical Lab Handbook

Container/Tube: Serum gel (SST) tube-Hemolyzed specimen is not acceptable.

Alternate Container: Lithium heparin (Mint) /Red top

Specimen Volume: 3.5 mL or 5 mL

Collection Instructions: Allow blood to clot for 30 minutes. Spin tube after the 30 minute interval.

Handling Instructions: Centrifuge specimens and remove the serum or plasma from the cellular material within 3 days of collection

The VITROS AST Slide is a multilayered, analytical element coated on a polyester support. A drop of patient sample is deposited on the slide and is evenly distributed by the spreading layer to the underlying layers. In the assay for aspartate aminotransferase, the amino group of L-aspartate is transferred to α-ketoglutarate in the presence of pyridoxal-5-phosphate (P-5-P) to produce glutamate and oxaloacetate. The oxaloacetate formed in the deamination of the L-aspartate is converted to pyruvate and carbon dioxide by oxaloacetate decarboxylase. Pyruvate is oxidized to acetylphosphate and hydrogen peroxide by pyruvate oxidase. The final reaction step involves the peroxidasecatalyzed oxidation of a leuco dye to produce a colored dye. The rate of oxidation of the leuco dye is monitored by reflectance spectrophotometry. The rate of change in reflectance density is proportional to enzyme activity in the sample. The low wavelength cutoff filter on the slide support minimizes the blank rate effects of incident light during the dye development.

Aspartate aminotransferase is present in high activity in heart, skeletal muscle, and liver. Increased serum AST activity commonly follows myocardial infarction, pulmonary emboli, skeletal muscle trauma, alcoholic cirrhosis, viral hepatitis, and drug-induced hepatitis.

Males: 17-59 U/L

Females: 14-36 U/L

Monday through Sunday

Available STAT

84450