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Method for Aspartate Aminotransferase activity determination

Kinetic method (Expert Panel of the International Federation of Clinical Chemistry)

1

Reaction principle

1 2-oxoglutarate + L-aspartate -- (GOT) -- L-glutamate + oxaloacetate
2 Oxaloacetate + NADH + H -- (MDH) -- L-malate + NAD

2

Contents

Reagent 1/Enzyme reagent
Reagent 2/Starting reagent

3

Stability of reagent start

The reagents are stable even after opening up to the stated expiry date when protected from light at 2-8 Celsius.

4

Stability of sample start

The working reagent is stable for 4 weeks at 2-8 Celsius and 5 days at 15-25 Celsius.

5

Specimen

1 Serum
2 Heparinized plasma
3 EDTA plasma

6

Loss of activity

1 Within 3 days at 4 Celsius: 8%
2 At 20-25 Celsius: 10%

7

Reference range

(Review)

8

Conversion factor

(Review)

9

Contain sodium azide

Enzyme reagent and starting reagent

10

Optical path

1 cm

11

Wavelength

Hg 365 nm, 340 nm or Hg 334

12

Temperature

1 25 Celsius
2 30 Celsius
3 37 Celsius

13

Measurement

Against air (decreasing absorbance)

14

Procedure

Mix, read the absorbance after 1 minute and at the same time start the stop watch. Read the absorbance again exactly after 1, 2, and 3 minutes.

15

Calculation measurements

For absorbance changes per minute within 0.06-0.08 (Hg 36 nm) or 0.12-0.16 (Hg 334 nm, 340 nm) (procedure 1+2) only measurements from the first 2 minutes are used for calculation (1 minute incubation, 2 minutes measurement).