Assembly Of Electrochemical Luminescence Molecules/Layered Double Hydroxide Ultrathin Films And Their Application In Sensors

Electrochemiluminescence (also called electrogeneratedchemiluminescence, abbreviated as ECL) is an electrochemically reactionunder certain voltage, which involves the generation of species atelectrode surfaces that then undergo electron transfer reactions to formexcited states that emit light. The ECL has been broadly used in chemicalanalysis, environmental and clinical immunoassays. In this thesis, thedesign and fabrication of two kinds of ultrathin films (UTFs), i.e.electrogenerated chemiluminescence molecular (ELM)/LDH andELM LDH/polyanion, have been achieved via layer by layer (LBL)self assembly technique. The electrochemistry and electrogeneratedchemiluminescence performances of the UTF modified electrodes wereinvestigated.The ECL active species, Ru(bpy)²⁺₃, was immobilized into the(CoAl LDH/PSS/Ru(bpy)²⁺₃/PSS)_n multilayer films by the LBL assemblymethod, which was applied as an ultrasensitive ECL sensor for the determination of dihydronicotinamide adenine dinucleotide (NADH). Themultilayer film modified electrode displays a wide linear response range(3.16×10^–63.23×10^–4mol/L) and low detection limit (2.3×10^–8mol/L).The (LDH/PSS/Ru(bpy)²⁺₃/PSS)₁0modified electrode also exhibits goodstability of this solid state ECL sensor. By virtue of the highly tunablecompositions and versatility of the LDHs nanosheets, theseorganic inorganic films can be potentially applied in the fields ofelectrochemical analysis and biosensors.The (3AMS NiAl LDH/PSS)_n multilayer films were fabricated vialayer by layer deposition technique by using sodium luminol(3AMS) intercalated LDH composite nanoparticles and polyanion (PSS)as building blocks. The obtained films show a long range stacking orderin the normal direction of the substrate. The (3AMS NiAl LDH/PSS)nmultilayer films in this work display a wide linear response range(3.09×10^–7-7.24×10^–5mol/L), low detection limit (6.8×10^–8mol/L) andhigh stability. This work provides a facile approach for theimmobilization of electrochemiluminescence species within a2Dinorganic layered matrix, in order to suppress the aggregation of ELMand explore potential applications in biological field.