The Human IGFBP3 ELISA Pair Set is for the quantitative determination of Human IGFBP3.This ELISA Pair Set contains the basic components required for the development of sandwich ELISAs.The Sino Biological ELISA Pair Set is a solid phase sandwich ELISA (Enzyme-Linked Immunosorbent Assay). It utilizes a monoclonal antibody specific for IGFBP3 coated on a 96-well plate. Standards and samples are added to the wells, and any IGFBP3 present binds to the immobilized antibody. The wells are washed and a horseradish peroxidase conjugated rabbit anti-IGFBP3 monoclonal antibody is then added, producing an antibody-antigen-antibody sandwich. The wells are again washed and TMB substrate solution is loaded, which produces color in proportion to the amount of IGFBP3 present in the sample. To end the enzyme reaction, the stop solution is added and absorbances of the microwell are read at 450 nm.