| Luminol is one of most extensively used chemiluninescence(CL) reagents. The CL signal of luminol reaction can be increased in the presence of transition metal ions, enzymes, and so on. Recent research showed that nano-material, quantum dot, ionic liquid, and cyclodextrins could also be used as sensitizers in some CL systems. In the first section of this thesis, the the analytical application of this new CL sensitizers in CL analysis in past several years was summarized. In the second section of this thesis, the two new CL reactions were investigated thoroughly. One reaction is luminol-isoniazid-gold nanoparticles(AuNPs) CL reaction. Another reaction is luminol-H2O2-horseradish peroxidase(HRP)-ionic liquid CL reaction.Part one. It was found that strong CL was directly produced by the reaction of isoniazid with luminol in the presence of AuNPs in an alkaline solution. The reagent concentrations, including luminol concentration, NaOH concentration and AuNPs concentration, were optimized with the aid of Box-Behnken design and response surface methodology. Under the optimal conditions, the proposed method allows the measurement of 5×10-9～3×10-7g/mL isoniazid with a detection limit of 4×10-9g/mL. The relative standard deviation is 1.3% for 1.0×10-/g/mL isonazid solution in 11 repeated measurements. The proposed method was applied to the analysis of isoniazid in tablets, injections and in spiked human blood serums. The possible CL reaction mechanism was discussed by the study of the UV-vis spectra, the CL spectra, and the effect of dissolved oxygen and reactive oxygen species scavengers on the reaction. The presence of AuNPs not only accelerated the rate of the reaction of isonazid with dissolved oxygen to produce H2O2, but also offered a nano-catalyzed planform for the decomposition of H2O2 to reactive oxygen species. The produced reactive oxygen species reacted with alkaline luminol to generate CL.Part two. The behavior of four imidazolium ionic liquids(ILs), namely 1-butyl-3-methylimidazolium tretrafluorophosphate([Bmim]BF4), 1-butyl-3-methyl-imidazolium chloride([Bmim]Cl), 1-Ethyl-3-Methylimidazolium tretrafluoro-phosphate ([Emim]BF4), and 1-Ethyl-3-Methylimidazolium Ethylsulfate, ([Emim]EtSO4) in Luminol-H2O2-HRP CL system, Luminol-H2O2-HRP-p-iodine phenol(PIP), Luminol-H2O2-HRP- Sodium tetraphenylborate (NaTPB) CL system were studied. The results showed that all of four ILs could increase the CL signal of above-mentioned three CL systems and [Emim]BF4 had the strongest enhancement. The effect of the concentrations of four ILs and pH of CL systems were optimzed. For Luminol-H2O2-HRP-[Emim]BF4 CL system, the linear range was 5×10-9～1.2×10-7 mol/L HRP, the detection limit was 1.4×10-9 mol/L, and the relative standard deviation was 3.2%(n=11,2.5×10-8 mol/L HRP solution). For luminol-H2O2-HRP-[Emim]BF4-PIP CL system, the linear range was 1.3×10-10～1.3×10-8 mol/L HRP, the detection limit was 4.0×10-11 mol/L, and the relative standard deviation was 3.4%(n=11,2.5×10-9 mol/L HRP solution). For luminol-H2O2-HRP-[Emim]BF4-NaTPB CL system, he linear range was 2.5×10-10～2.3×10-8 mol/L HRP, the detection limit was 1.4×10-10 mol/L, and the relative standard deviation was 0.5%(n=11, 2.5×10-9 mol/L HRP solution). The presence of ILs did not produce new CL emitter(The excited state of 3-aminophthalate ion was still the CL emitter of the present reaction), but increased the fluorescence quantum yield of 3-aminophthalate ion, consequently resulted in an enhancement in CL signal. |
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