The Co3O4 nanoparticle-enhanced luminol-O2 chemiluminescence reaction used for the determination of nortriptyline hydrochloride and lamotrigine in pharmaceutical and environmental samples

Abstract

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 × 10⁻⁶–1.0 × 10⁻⁴ mol L⁻¹, with a limit of detection (LOD) = 5.2 × 10⁻⁷ mol L⁻¹ for NT and 7.0 × 10⁻⁷–1.0 × 10⁻⁴ mol L⁻¹, with a LOD = 2.8 × 10⁻⁷ mol L⁻¹ for LTG. The relative standard deviation (RSD) of the CL methods was 3.6 and 2.7 (n = 9) for the determination of 1.0 × 10⁻⁶ mol L⁻¹ NT and LTG, respectively. The CL method was used for the measurement of NT and LTG in pharmaceutical preparations and spiked tap waters.