Human HFABP immunoassay is a 3.5 - 4.5 hour solid phase ELISA designed to measure human HFABP in cell culture supernates, serum and EDTA plasma. It contains recombinant Human HFABP and antibodies raised against this protein. It has been shown to accurately quantitie recombinant Human HFABP. Results obtained with naturally occurring HFABP samples showed linear curves that were parallel to the standard curves obtained using the kit standards. These results indicate that the Immunoassay kit can be used to determine relative mass values for natural Human HFABP.