03/21/2026
Liver Function Test (LFT)
1. Objective
The objective of this experiment was to evaluate liver function by measuring enzymes and bilirubin levels in the patient’s serum.
2. Principle
The Liver Function Test was based on biochemical reactions between liver enzymes or bilirubin and specific reagents. These reactions produced a colored compound whose intensity was measured using a spectrophotometer, indicating the concentration of the analyte.
3. Materials
Patient serum sample
Test tubes or cuvettes
Micropipette and tips
ALT reagent
AST reagent
ALP reagent
Bilirubin reagent
Spectrophotometer / analyzer
Centrifuge
Test tube rack
4. Procedure (Points)
1. Blood was collected from the patient and allowed to clot.
2. The sample was centrifuged to separate the serum.
3. Serum was transferred to labeled test tubes.
4. Specific reagents for ALT, AST, ALP, and bilirubin were added.
5. The mixture was incubated for the required time.
6. The reaction produced a color change.
7. The absorbance was measured using a spectrophotometer.
8. The enzyme levels were calculated from the readings.
5. Result
The concentrations of ALT, AST, ALP, and bilirubin were obtained and compared with normal reference ranges to assess liver function.
6. Uses
It was used to diagnose liver diseases.
It helped detect hepatitis and cirrhosis.
It was used to monitor liver damage and treatment response.
It helped evaluate jaundice and bile duct obstruction.
7. Consultation (Normal Range)
Parameter Normal Range
ALT (SGPT) 7 – 56 U/L
AST (SGOT) 10 – 40 U/L
ALP 44 – 147 U/L
Total Bilirubin 0.3 – 1.2 mg/dL
Direct Bilirubin 0.1 – 0.3 mg/dL
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