The Quantikine Human FGF-19 Immunoassay is a 4.5 hour solid-phase ELISA designed to measure human FGF-19 in cell culture supernates, serum, and plasma. It contains E. coli-expressed recombinant human FGF-19 and has been shown to accurately quantitate the recombinant factor. Results obtained using natural human FGF-19 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 FGF-19. Range: 15.60 - 1000 pg/mL. Sensitivity: 3.35 pg/mL. Time: 4.5 hours