Ru (bpy) ₃ ^{2 + _{Research -SiO 2} Nanoparticles ECL Analysis Features}

Ru(bpy)32+-based electrogenerated chemiluminescence (ECL) system has been attracted considerable attention during the past several decades because its higher quantum yields, high chemical stability, wide application and Ru(bpy)32+could be regenerated during the ECL process. Up to now, extensive efforts have been directed towards to the immobilization materials of Ru(bpy)32+so as to fabricate the regenerative ECL sensors.Now, a number of materials have been used to immobilize Ru(bpy)32+or its derivatives on electrode surfaces for fabricating ECL sensors. In these materials, the silica nanoparticles have been paid more attention due to its excellent properties:First of all, silica nanomaterials are effectively "transparent", which allows the Ru(bpy)32+inside silica matrix to keep their original optical properties. Second, silica nanoparticles entrap a large number of Ru(bpy)32+in the silica matrix, which produce a strong ECL signal. Incorporation of Ru(bpy)32+inside the silica matrix protects the Ru(bpy)32+from the surroundings, making the signal of ECL very stable and, thereby, offering accurate measurements for bioanalysis. Thirdly, the silica matrices are nontoxic and biocompatible for biomedical research, and the well-established silica chemistry facilitates the modification of silica-based nanohybrids with different functional moieties. However, the silica nanoparticles are rigid and own very smaller pore size. So the silica nanoparticles faced the serious nonspecific adsorption in reported ECL co-reactants. The mass-transfer speed of co-reactants in silica matrix is slow, thus the ECL performances of the silica-based ECL sensors was limited, with the low sensitivity and stability. For overcoming this limitation, two schemes, developing new ECL co-reactant and increasing the pore size of the silica matrix, were proposed in this thesis.This thesis consists of two parts, review and study. Chapter1is the review, brief introduced the concept and property of Eletrogenerated Chemiluminescene (ECL) reaction, the principles and property of Ru(bpy)32+-ECL sensor, the immobilized materials of Ru(bpy)32+and the analytical applications of Ru(bpy)32+-ECL sensors. Mainly introduced the advantages of silica, the recent developments of Ru-DSNPs ECL sensor. Finally elaborated the research background and basic idea of this paper. The research section contains two Chapters:Chapter2and Chapter3.Chapter2:Electrogenerated Chemiluminescence Analytical Performances of Porous Ru(bpy)32+-Doped Silica Nanoparticles.The porous Ru-DSNPs nanoparticles were prepared by by the alkaline etching route and were immobilzed on the surface of electrod, Meanwhile, electrogenerated chemiluminescence analytical performances of the porous nanoparticles was studied. Our results showed that about6nm nanopores inside the about70nm Ru-DSNPs could provide the effective mass-transfer channel to allow the ECL co-reactant to get easily into inner part of Ru-DSNPs to take part in the ECL reaction. Then, the TPA was selected as the model to explore the ECL performances of this porous RuDSNPs. Under the optimum conditions, the ECL sensor offered a3.3×10’12mol/L detecting limit, it is one order of magnitude higher than that of previous reported Ru-DSNPs ECL sensor for tripropylamine.Chapter3:Electrogenerated chemiluminescence sensor for Cu2+with Ru(bpy)32+-doped silica nanoparticles/Nafion composite films modified electrode.It was found that the Cu(Tris)42+complex had electrochemical activity were prepared by keep Cu2+in Tris-HCl buffer (0.05mol/L, pH=7.4), and its oxidation reduction reaction can be catalyzed by Ru(bpy)32+. In addition, electrochemiluminescence study shows that the complexes can sensitization the Ru-DSNPs/Nafion composite film of Ru(bpy)32+electrochemical luminescence response with stable electrochemical luminescence signal. Based on these findings and Optimize the related conditions. A ECL sensor was fabricated for the determination of Cu2+in Tris-HCl buffer (0.05mol/L, pH=7.4). Under the optimum condition, the enhanced ECL intensity was linear with the Cu2+concentration in the range of2.0×10-7mol/L-1.0×10-4mol/L (r2=0.9938). The detection limit was1.0×10-7mol/L, and the relative standard deviation was1.0%for1.0×10-5mol/L Cu2+(n=11) in Tris-HCl buffer (0.05mol/L, pH=7.4). The method was successfully applied to the determination of Cu2+in tap water samples with satisfactory results. The as-prepared ECL sensor for the determination of Cu2+displayed good sensitivity and stability.