Samples must be at room temperature before beginning the test procedure.

Serum or plasma, either fresh, previously frozen or stored at 2°–7°C (35°–45°F) can be used in this test.

Serum or plasma can be stored for up to seven days at 2°–7°C (35°–45°F). For longer storage, the sample should be frozen (-20°C/-4°F or colder).

Previously frozen or older samples must be centrifuged before use.

Hemolyzed or lipemic samples will not affect results.

EDTA or heparin in plasma will not affect results.