4. NAT Pre-analysis Flashcards
1
Q
Max storage time for whole blood at room temperature
A
Up to 24 hrs
2
Q
Why should the buffy coat be separated from whole blood specimens if there will be a delay in NA isolation
A
Buffy coat will contain WBCs containing nucleic acids
If whole blood is frozen, cells will lyse upon thawing:
- hemoglobin co-isolating with DNA will inhibit PCR
- Lysed WBCs will have nucleic acids degraded by nucleases
3
Q
Why is DNA isolated from heparin anti-coagulated blood not suitable for PCR
A
Heparin co-isolates with DNA during purification and it inhibits the activity of polymerase
4
Q
Max storage time for whole blood at fridge temperature
A
Up to 72 hrs