Print

VETSPEC™REAGENTS - Aspartate Aminotransferase (AST/SGOT) AcNADH Method

Intended Use

For IN VITRO diagnostic use in the quantitative determination of AST (SGOT) in serum or plasma using manual or automated applications.

Method Principle

The Aspartate Aminotransferase (AST) enzyme catalyzes the conversion of alpha-Ketoglutarate and L-Aspartate to L-Glutamate and Oxalacetate. The Oxalacetate produced is then quantitatively determined by the MDH-AcNADH reaction. The decrease in absorbance due to the oxidation of AcNADH to AcNAD is monitored at 340 nm. The rate of decrease in absorbance of the reaction mixture is directly proportional to the AST enzyme activity in the serum sample. The reaction scheme below illustrates the reactions that occur in this method.

AST
L-Aspartate + alpha-KG ────────> L-Glutamate + Oxalacetate

      MDH
Oxalacetate + AcNADH ────────> L-Malate + AcNAD

 

AST Reagent Storage And Stability

The AST Liquid Stable Reagent is stored at 2-8°C. When stored as directed, this reagent is stable until the  expiration date stated on the label.

Method Performance Characteristics

Sensitivity: The sensitivity of this method is 0.0002 absorbance units per u/L.
Linear Range: In this method there is no significant nonlinearity over the range of 0-1000 u/L.
Precision: Within-run and day-to-day precision is summarized on next page.

AST

Within-Run Precision

Total Precision

MEAN

SD

CV

SD

CV

U/L

U/L

%

U/L

%

26

1.0

3.8

1.8

6.9

69

2.4

3.5

3.1

4.5

385

9.2

2.3

11.6

3.0

 

Correlation

A comparison of this method using a discrete random access analyzer and a reference procedure based upon the recommendations of IFCC resulted in the following regression statistics:

Correlation Data

Parameter

Data Observed

N

122

Range

15-440 U/L

Regression

Y = 0.99x + 0.94

Correlation

  r = 0.99

Sy,x

3.4