Human C-Peptide PharmaGenie ELISA Kit (SBRS0020)

1. Pre-Coated 96-well Strip Microplate
2. Wash Buffer
3. Standard Peptide
4. Assay Diluent(s)
5. Biotinylated Peptide
6. HRP-Streptavidin
7. TMB One-Step Substrate
8. Stop Solution
9. Assay Diagram
10. Positive Control Sample
11. Capture Antibody
12. Technical Manual

Other materials and equipment required:

The Assay Genie Human C-Peptide PharmaGenie ELISA Kit (SBRS0020) will require other equipment and materials to carry out the assay. Please see list below for further details.

• Distilled or deionized water
• Precision pipettes to deliver 2 ul to 1 ml volumes
• Adjustable 1-25 ml pipettes for reagent preparation
• 100 ml and 1 liter graduated cylinders
• Tubes to prepare standard and sample dilutions
• Orbital shaker
• Aluminum foil
• Saran Wrap
• Absorbent paper
• Microplate reader capable of measuring absorbance at 450nm
• SigmaPlot software (or other software that can perform four-parameter logistic regression models)

1. Prepare all reagents, samples and standards as instructed.
2. Add 100 ul detection antibody to each well.
3. Incubate 1.5 h at RT or O/N at 4°C.
4. Add 100 ul standard or sample to each well.
5. Incubate 2.5 h at RT.
6. Add 100 ul prepared streptavidin solution.
7. Incubate 45 min at RT.
8. Add 100 ul TMB One-Step Substrate Reagent to each well.
9. Incubate 30 min at RT.
10. Add 50 ul Stop Solution to each well.
11. Read plate at 450 nm immediately.

C-Peptide is a 31-amino acid single-chain peptide that is made when proinsulin is split into insulin and C-Peptide. They split before proinsulin is released from endocytic vesicles within the pancreas-one C-Peptide for each insulin molecule. C-Peptide is the middle segment of proinsulin that is between the N-terminal B-chain (30 amino acids) and the C-terminal A-chain (21 amino acids). Unlike insulin, C-Peptide has no known physiological function. Due to the fact that C-Peptide has a 2-to-5-time longer half-life than insulin, there are higher concentrations of C-Peptide than insulin in the peripheral circulation. Therefore, plasma C-Peptide concentrations may reflect pancreatic insulin secretion more reliably than the level of insulin itself. C-Peptide is cleared from the body by the kidney, and, unlike insulin, urine concentrations are 20 - 50 times higher than in plasma. Unlike plasma insulin levels, which fluctuate in response to meals, measurement of the 24-hour urinary excretion of C-Peptide provides a useful monitor of average beta cell insulin secretion. The level of C-Peptide has been used to assess the following clinical applications: to assess the residual beta cell function in patients treated with insulin and to distinguish between types 1 and 2 diabetes. Of particular interest is its use to indicate the need for progression to insulin therapy in type 2 diabetes. The diagnosis of factitious hypoglycemia. The surreptitious administration of insulin causes high insulin levels in the absence of elevated C-Peptide concentrations. Insulinoma diagnosis, especially in patients treated with insulin. C-Peptide measurement is used in insulin suppression tests in euglycemic patients with suspected insulinoma. Elevated C-Peptide levels in this test are indicative of insulinoma. As a marker for residual pancreatic tissue after pancreatectomy. In the case of insulinoma, C-Peptide measurement may be used to detect metastasis and the response to therapy. It may also be used to monitor the progress of pancreas or islet cell transplantation