KE00270 is a solid phase sandwich Enzyme Linked-Immuno-Sorbent Assay (Sandwich ELISA). The RBP4 ELISA kit is to be used to detect and quantify protein levels of endogenous RBP4. The assay recognizes human RBP4. An antibody specific for RBP4 has been pre-coated onto the microwells. The RBP4 protein in samples is captured by the coated antibody after incubation. Following extensive washing, another horseradish peroxidase (HRP)-conjugated antibody specific for RBP4 is added to detect the captured RBP4 protein. For signal development, followed by Tetramethyl-benzidine (TMB) reagent. Solution containing sulfuric acid is used to stop color development and the color intensity which is proportional to the quantity of bound protein is measurable at 450 nm with the correction wavelength set at 630 nm.