NGAL is a biomarker of kidney tubular damage and a predictor of a condition termed AKI. In neutrophils, NGAL can occur in both monomer and homodimer forms as well as in complex with MMP-9. The NGAL (human) monomer-specific ELISA Kit is a sandwich assay that can be used to measure NGAL monomers in human urine, EDTA plasma, or Li-heparin plasma samples. The specific antibodies provided in this kit do not react with NGAL homodimers or heterodimers. The assay exhibits sensitivity sufficient to detect levels of NGAL monomers as low as 4 pg/ml.