Green top tube (sodium or lithium heparin)
1 mL plasma
0.5 mL plasma
Fasting specimen. Place on ice immediately. Must arrive in lab or aliquot and freeze within 2 hours.
Collect specimen in green top tube from a fasting patient (red top tube is acceptable). Place specimen on ice immediately after collection and keep cold until ready to aliquot. Centrifuge, aliquot plasma into a plastic vial and freeze within 1 hour of collection.
Collect specimen in green top tube from a fasting patient. Place specimen on ice and transport to the laboratory, or centrifuge, aliquot into a plastic vial and freeze within 1 hour of collection.
Monday, Wednesday, Friday
8 hours
Chemiluminescence
1.0-5.2 ng/ml (fasting)
Evaluate residual beta cell function in patients with diabetes mellitus treated with insulin, low in instances of surreptitious injection of insulin, elevated in insulin autoimmune hypoglycemia, workup of hypoglycemia and to aid in the diagnosis of insulinoma with glucose and insulin assays.
Z15-8
84681
23359
SST (not preferred). Heparinized plasma transported on ice is the preferred collection and handling; specimens must be assayed or aliquotted and frozen within 2 hours of collection. If CD personnel are unsure of a sample's validity for c-peptide testing, please consult with chemistry staff. [10/05]