The Quantikine Human Proinsulin Immunoassay is a 4.5 hour solid-phase ELISA designed to measure human Proinsulin in serum and plasma. It contains E. coli-expressed recombinant human Proinsulin and has been shown to accurately quantitate the recombinant factor. Results obtained using natural human Proinsulin showed linear curves that were parallel to the standard curves obtained using the Quantikine kit standards. These results indicate that this kit can be used to determine relative mass values for naturally occurring human Proinsulin. Range: 3.28 - 210 pM. Sensitivity: 1.43 pM. Time: 4.5 hours