Test code:


Abbreviations, alternative names:

Plasma GFAP, NP2B


Single-molecule array (Simoa)


Specimen type:

EDTA plasma

Minimum volume:

0.5 mL

Preferred volume:

5 mL

Rejection criteria:

Grossly hemolytic, lipemic, or icteric. If the sample arrives at room temperature

Our offices are only able to receive samples Mon-Fri, so samples must be shipped Mon-Thur. Samples arriving over the weekend may need to be re-drawn.


GFAP is extremely sensitive to temperature and free/thaw cycles. It is critical that time at room temperature be minimized. Refrigerate when not handling, and immediately after sample has been centrifuged and aliquoted.

Specimen collection:

Overnight fasting is recommended
Draw blood in K2 EDTA tubes (lavender top)
Invert 8 times to ensure complete mixing

Specimen handling:

Centrifuge EDTA tubes at 1800 - 2200 x g for 10-15 minutes (use refrigerated centrifuge, if available)
Draw off plasma into Aliquot tubes with pipette, ensuring not to take gel or RBC (middle/bottom layers)
Store Aliquot tubes in refrigerator (2°C - 8°C) until shipping

Specimen storage:

Plasma samples must either be refrigerated and shipped chilled within 24 hours of collection, or frozen and shipped on dry ice


Testing frequency:

Once per week

Turnaround time:

1 week

Reference range:

To Be Established


Research use only (RUO)

Additional Information

  • Test results are for research use only. Not to be used for diagnostic purposes.

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