| In this dissertation, the state of arts in the field of chemiluminescence(CL), nanoparticle-involved CL, the synthesis and properties of metal nano-materials and their applications in analytical chemistry were reviewed. In the past, the research of liquid-phase CL was limited on the molecular or ionic system. Resently, accompanying by the development of nano science, nanoparticle-involved liquid-phase CL has received considerable interest. Metal nanoparticles can participate in CL reaction as catalysts, reductant, nanosized platform and energy acceptor. However, most of the reported CL systems were focused on luminol and the nanoparticles used were limited to gold nanoparticle. Other famous CL systems and other metal nanoparticles had been rarely reported. In the present dissertation, it was found that platinum nanoparticle could initiate lucigenin--hydrazine system to generate CL. The CL mechanism was investigated. Moreover the effects of some organic compounds on the CL reaction were examined, It was found that thiol-containing compounds could strongly enhance the CL intensity. On this basis, a flow injection procedure was developed for the detection of thiol-containing compounds. The main results are as follows:1. It was found that lucigenin alkaline solution could react with hydrazine in the presence of Plarinum nanoparticles(Pt NPs) to generate strong CL, UV-visible spectra, Fluorescence spectra, X-ray photoelectron spectra and CL spectra studies were carried out. The effects of O2 and superoxide dismutase (SOD) on the CL reaction were examined. A possible mechanism is proposed that Pt NPs catalyzed the reaction between hydrazine and the dissolved oxygen under alkaline conditions to yield hydroperoxide species and superoxide radical anion, which further oxidized lucigenin to produce CL emission. Pt NPs did not change before and after the CL reaction and the enhanced CL originated from the catalytic effects of Pt NPs, which accelerated electron-transfer process and facilitated the CL radical generation. This new CL system is intense, stable and sensitive. The effects of some organic compounds containing hydroxyl (OH), carboxyl (COOH), carbonyl (CO), amino (NH2), or sulfur groups on the lucigenin– hydrazine– Pt NPs CL system were tested. It was found that the compounds containing hydroxyl (OH), carboxyl (COOH), carbonyl (CO) group showed no obvious effects on the CL system, Aniline and its derivatives and Aliphatic amine compounds slightly enhance the CL. Most enhancement effects were observed from Sulfur-containing compounds.2,Based on the new CL system of Pt NPs catalyzed lucigenin—hydrazine, 6-mercaptopurine (6-MP) was chosen as a model compound for the study of the CL enhancement mechanism. It is proposed that Pt NPs as a catalyst could transfer electrons to hydrogen peroxide to produce hydroperoxide, which readily attack thiol-containing compounds to form sulfide radical anion. The sulfide radical anion can readily react with sulfide anion to form disulfide radical anion, which can transfer their unpaired electron to oxygen to give superoxide radical anion. The superoxide radical anion further oxidized lucigenin to produce CL emission. Based on the CL enhancement, a flow injection CL procedure was developed for the determination of Cys, GSH, Hcy and 6-MP. Under the optimized conditions, the linear ranges of Cys, GSH, Hcy and 6-MP were 4.0×10-91.5×10-6g/mL, 5.0×10-91.3×10-6g/mL, 2.0×10-91×10-6g/mL and 4.0×10-83.0×10-6g/mL respectively. The limits of detection (LODs) at a signal-to-noise ratio of 3 (S/N=3) were 1.8, 3.0, 0.9, 8.0 ng/mL, respectively. The present method is simple, rapid and sensitive.. |
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