Patient should avoid alcohol, coffee, tea, tobacco and strenuous exercise prior to collection. Overnight fasting is preferred. Patients should be relaxed in either a supine or upright positiion before blood is drawn.

Draw blood in a pre-chilled lavender EDTA tube, Sample should be kept on wet ice until centrifugation. Spin and separate the plasma from the cells within 2 hours of collection. Send 2.5 mL plasma (1.5 mL minimum) refrigerated in a screw-capped plastic vial.