Human serum or plasma
Collect blood into either a plain vacutainer (red top) for serum or a vacutainer containing EDTA(lavender top) for plasma. If collecting serum, allow the blood to clot at RT for 30 minutes, then centrifuge at 1500 x g for 15 minutes. To prepare plasma samples, centrifuge the EDTA blood immediately for 15 minutes at 1500 x g in a refrigerated centrifuge set at 4o C. Transfer either the serum or the plasma to a labeled 12 x 75 mm polypropylene tube. Store at -80o C until time of assay.
The LINCO radioimmunoassay is a direct measurement of leptin and requires 100 µl of serum or plasma in duplicate or 200 µl for one determination.
Suggested blood sample size: 3 ml
