مشخصات پژوهش

In recent years, there has been a great deal of interests in the development of chemiluminesce (CL)-based sensors due to their wide linear dynamic range, relative simple and inexpensive instrumentation, no interference from background scattering light and versatility for the determination of a wide variety of species [1]. Enhancement of CL intensity via the choice of the appropriate solvent, catalyst, or surfactant is of great importance to improve the sensitivity of CL detection systems. Recent reports show that nanomaterials can act as catalysts to amplify the emission of CL systems. Due to their unique physicochemical properties, many CL systems based on different kinds of nanomaterials have been developed [2]. Layered double hydroxides (LDHs) are an important class of host-guest layered nanomaterials consisting of positively charged metal hydroxide sheets with charge-balancing intercalated anions and water molecules. LDHs exhibit a well-defined layered structure with relatively large surface area, high porosity, high layer charge density and interlayer anion mobility [3]. In the present study, we reported on a simple, sensitive and selective chemosensor for determination of dopamine in human plasma samples. It is based on the inhibitory effect of dopamine on the chemiluminescence signal of KMnO4–luminol system, which could be improved by at least 10-folds in the presence of LDHs. The possible mechanism to explain this finding was studied. The structure and morphology of the synthesized LDHs were characterized by x-ray diffraction, Fourier transform infrared spectroscopy, transmission electron microscopy and scanning electron microscopy. Several parameters affecting the analytical signal such as concentration of luminol, KMnO4, NaOH and LDH were optimized. This simple CL approach showed a limit of detection of 8.5 ng L‒1 and exhibited a linear response in the concentration range from 0.025 to 20 μg L‒1. In addition, the method exhibited high specificity toward do