The Eagle Biosciences GABA ELISA Assay Kit employs the competitive enzyme immunoassay technique. An antigen GABA has been pre-coated onto a microtiter plate. Standards or samples are pipetted into the wells and any GABA present compete for the fixed number of antibody binding site. After washing away any unbound substances, the antibody bound to the solid phase is detected by using TMB as a substrate. The reaction is monitored at 450 nm±2 nm. Quantification of unknown samples is achieved by comparing their absorbance with a reference curve prepared with known standards. Sample Types: serum, plasma, urine. Range: 75-7500 ng/ml. Sensitivity: 49 ng/ml (urine); 25 ng/ml (serum/plasma). Time: 3 hours ?