Detection of liver cancer cells by using ELISA and coupling of anti-glypican 3 antibody and magnetite nanoparticles

A method for detecting glypican 3 (GPC3) liver cancer cells by coupling of anti-glypican 3 antibody (anti-GPC3) and magnetite nanoparticles (NPs) was investigated to detect GPC3 by enzyme-linked immunosorbent assay (ELISA) in this study. Magnetite NPs with the average size of 11 nm were synthesized by using co-precipitation method of Fe2+ and Fe3+ in NH3·H2O solution. First, silica was coated on the magnetite NPs using Stober method to obtain Fe3O4/SiO2 core-shell structures and then 3-aminopropyltriethoxysilane (APTES) was treated on the Fe3O4/SiO2 by silanization reaction to achieve Fe3O4/SiO2/APTES nanostructures. After modified by APTES, the nanostructures were activated by glutaraldehyde (GA) to obtain functional groups on the nanostructures surface to bind with anti-GPC3 by covalent immobilization. The UV–vis spectroscopy was carried out to investigate the binding of anti-GPC3 to the NPs and binding efficiency (88.35%) was estimated by the Bradford method. The NPs bound anti-GPC3 (NPs/anti-GPC3) can...