Tumor Necrosis Factor (TNF) ELISA Kit: The Human TNF-alpha Enzyme-Linked-Immuno-Sorbent-Assay (ELISA) Kit is intended for the quantitative determination of Tumor Necrosis Factor alpha (TNF-a) in human serum, plasma, and cell culture supernatants. TNF-a ELISA is for research use only.Recovery: Recovery rate was found to be higher than 98% when spiked using normal human serum samples with known concentrations.