Abstract:Using goat anti-mouse IgG monoclonal antibody as model protein,antibody modification conditions on the surface of carboxylated superparamagnetic nanoparticles(SMN) A and B were optimized,then hydrodynamic sizes and polydispersity index(PDI) of SMN-A and B before and after antibody modification were compared.Additionally,the biological activity of modifying antibodies was assessed by a competitive format lateral flow immunoassay(LFIA).Optimization results indicated that the best modification conditions were different for SMNs of different sizes and manufactures.Before and after modification,the hydrodynamic size change rate of SMN-A was 6.55%,PDI were 0.011 and 0.046,respectively,the change was minor,while hydrodynamic size change rate of SMN-B was 135.5%,and the dispersivity became worse.Furthermore,the antibody modifying on SMN-A and B both showed good biological activities by LFIA test,and SMN-A indicated better lateral flow performance.Briefly,if antibody modifying SMNs were chosen as labels in LFIA test,size and dispersivity change before and after modification,magnetic signal intensity of the material had great mean in improving detection sensitivity and assay rate.
