SGOT(SERUM GLUTAMIC OXALOACITIC TRANSAMINASE)
INTENDED USE:
This reagent kit is intended for in vitro quantitative determination of SGOT (AST) activity in serum.
PRINCIPLE:
SGOT (AST) catalyzes the transfer of amino group between L-Aspartate and α-ketoglutarate to form oxaloacetate and glutamate. The oxaloacetate formed reacts with NADH in the presence of Malate Dehydrogenase to form NAD. The rate of oxidation of NADH to NAD is measured as a decrease in absorbance which is proportional to the SGOT (AST) activity in the sample.
REACTION:
L-Aspartate + α-Ketoglutarate
—(Aspartate aminotransferase)→
Oxaloacetate + Glutamate
Oxaloacetate + NADH
—(Malate Dehydrogenase)→
L-Malate + NAD⁺
CONTENTS:
Reagent 1: SGOT Enzyme Reagent
Reagent 2: SGOT Substrate Reagent
MATERIALS REQUIRED BUT NOT PROVIDED:
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Clean & Dry Glassware
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Laboratory Glass Pipettes or Micropipettes & Tips
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Bio-Chemistry Analyzer
SAMPLES:
Serum free of hemolysis. SGOT (AST) is reported to be stable in serum for 3 days at 2–8°C.
PROCEDURE:
Pipette into clean dry test tube labeled as (T):
| Addition sequence | (T) |
|---|---|
| Working Reagent | 1 ml |
| Sample | 100 µl |
Mix well and read the initial absorbance A₁ at 1 min and repeat the absorbance reading after every 1 & 2 mins. Calculate the mean absorbance change per minute (ΔA/min.).
CALCULATION:
SGOT activity (U/L) = ΔA/min × 1746
NORMAL VALUE:
Serum: < 40 U/L
Each laboratory should establish its own normal range representing patient population.
CLINICAL SIGNIFICANCE:
SGOT is an enzyme found mainly in heart muscle, liver cells, skeletal muscle and kidneys. Injury to these tissues results in the release of the enzyme into blood. Elevated levels are found in myocardial infarction, cardiac operations, hepatitis, cirrhosis, acute renal diseases, primary muscle diseases. Decreased levels may be found in pregnancy, beri beri and diabetic ketoacidosis.
GENERAL SYSTEM PARAMETERS:
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Reaction Type: Kinetic (Decreasing)
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Wavelength: 340 nm
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Cuvette Temp: 37°C
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Delay Time: 60 sec
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Interval Time: 60 sec
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No. of Reading: 2
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Reagent Volume: 1 ml
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Sample Volume: 100 µl
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Zero Setting: Deionised Water
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Light Path: 1 cm
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Factor: 1746
LINEARITY:
The procedure is linear up to 300 U/L. If the activity exceeds this limit, dilute the sample with normal saline (NaCl 0.9%) and multiply result by dilution factor.
QUALITY CONTROL:
For accuracy it is necessary to run known controls with every assay.
LIMITATION & PRECAUTIONS:
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Storage conditions as mentioned on the kit to be adhered.
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Do not freeze or expose the reagents to higher temperature as it may affect the performance of the kit.
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Before the assay bring all the reagents to room temperature.
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Avoid contamination of the reagent during assay process.
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Use clean glassware free from dust or debris. PREPARATION OF REAGENT & STABILITY:
Working reagent:
Mix 4 parts of Reagent 1 with 1 part of Reagent 2. Working solution is stable for 4 days at 2–8°C.