Spherical, cubic and plate-like Co3O4 nanoparticles (NPs) were synthesised and, then, were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR). It was found that Co3O4 NPs possess oxidase-like activity and could enhance the intensity of the CL reaction. The enhancing effect of Co3O4 NPs on the CL reaction was dependent on the shape of the Co3O4 NPs. It increased in the order of Co3O4 nanoplates (NPLs) < Co3O4 nanocubes (NCs) < Co3O4 nanospheres (NSs). Moreover, it was found that nortriptyline (NT) and lamotrigine (LTG) could quench the Co3O4 NSs-luminol-O2 CL reaction. Based on these findings, simple and sensitive CL methods for the determination of NT and LTG were proposed. The linear dynamic ranges of the CL methods were 1.0 106–1.0 104 mol L1, with a limit of detection (LOD) ¼ 5.2 107 mol L1 for NT and 7.0 107–1.0 104 mol L1, with a LOD ¼ 2.8 107 mol L1 for LTG. The relative standard deviation (RSD) of the CL methods was 3.6 and 2.7 (n ¼ 9) for the determination of 1.0 106 mol L1 NT and LTG, respectively. The CL method was used for the measurement of NT and LTG in pharmaceutical preparations and spiked tap waters.
