Magnetic Beads Transfer Based Assay for Cry1 Ab Protein

A novel method for the immunoassay of genetically modified organisms (GMOs) protein Cry1Ab was proposed. First, nano magnetic beads with the diameters around 400 nm were prepared by the hydrothermal method. Then, the magnetic beads prepared were modified with -NH2 group using the sol-gel approach. The antibody was conjugated on the surface of magnetic beads through bi-functional agent glutaraldehyde. The immunoassay was carried out in the commercial nucleic acid extractor. The detection limit of this method for Cry1Ab is as low as 1 ppb, which is comparable to that of the common ELISA methods. This automatic way is promising because of its rapidity and simplicity.