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Laboratory Code
LAB481
Specimen Requirements
Specimen Type: Plasma
Container/Tube: Green Top (Li Heparin)
Volume: 4.5 mL
Minimum Volume: 0.5 mL plasma
Collection Instructions: Protect sample from light with aluminium foil and send to laboratory immediately.
Specimen Stability
| Specimen Type | Plasma |
|---|---|
| Ambient | 1 day |
| Refrigerate | 2 days |
| Frozen | 6 months |
Methodology
Chemiluminescent Immunoassay
Days and Times Performed
24 hrs, TAT 1 day
Specimen Condition
| Haemolysis | OK |
|---|---|
| Icterus | OK |
| Lipaemia | OK |
| Others: Specimen not protected from light | Reject |
Reference Interval
| Post treatment | 5.00 – 10.00 umol/L |
|---|---|
| 24 – 48 hrs | 0.50 – 1.00 umol/L |
| 48 – 72 hrs | < 0.20 umol/L |
Testing Laboratory
National University Hospital
Clinical Chemistry, 67724346
Useful For
Therapeutic drug monitoring.
Service Code
31819
LOINC Code Information
14836-1
Update
Last updated 11/03/2025