▎ 摘　　要

We report on an efficient method for the production carboxy-modified graphene (carboxy-GR), and its application to a highly sensitive immunoassay for the livestock feed additive clenbuterol. Octadecanoic acid is shown to self-assemble on carboxy-GR via intermolecular interaction. Goat anti-mouse IgG was conjugated to 1-octadecanethiol-modified carboxy-GR and then deposited by self-assembly on a C18-modified gold surface. The resulting sensor surface was used to quantify clenbuterol by both surface plasmon resonance and electrochemical impedance spectroscopy. The assay works in the 0.01 nga (TM) mL(-1) to 10 nga (TM) mL(-1) concentration range and the lower detection limit is 6.57 pga (TM) mL(-1). It is concluded that this fairly simple method can be extended to immunoassays for other food additives.