Collect 4mL blood in a serum separator tube or 4mL in a plain red top tube. Separate serum from cells immediately by centrifuge, and aliquot into a labeled polypropylene or similar plastic tube.
Preferred volume: 1 mL serum
Minimum volume: 0.3mL serum
Grossly hemolyzed specimens
Frozen. Send frozen serum Priority Overnight via FedEx and in a well insulated container, on dry ice.
8 hours refrigerated at 2-8°C
>8 hours frozen at -20°C
2 Step Competitive Chemiluminescent
48-72 hrs from when specimen is received in the laboratory.
Folic Acid (Folate, serum)
4 - 20 ng/mL