The Research And Application Of Molecular Imprinting- Electrochemiluminescence Sensor

Electrogenerated Chemiluminescence(ECL), is caused by the electrochemical and chemical luminescence, has attracted many extensive studies in analytical applications.The ruthenium tris (bipyridine) (Ru (bpy)3²⁺) and its derivatives which are the most extensively studied complexes in ECL. However, we should note that the reagent consumption will lead to increased costs in analysis process. We found that the iridium complexes and bipyridine ruthenium complexes have similar ground state and excited state Eh, while most iridium complexes are water-insoluble, therefore the research and applications of solid-state Electrochemiluminescence of iridium complexes have very great significance.Molecularly imprinting technique has become important in recent years. Generally, the imprinting process consists of rearrangement of the target molecules with functional monomers prior to initiation of polymerization. So in this background, the paper will be coupled with ECL and MIT, molecular imprinted polymer specific template molecule on the target identification and capture of template molecular will be selectively separted from the complex systems. The main results were given as follows:1. Explained the principles and characteristics, highlighting the immobilized metal complex method. ECL introduced the research progress of experimental apparatus, quantitative analysis. Through literature review, form the research development, characteristic and the exisiting problems to introduce the molecular imprinting technology.2. Constructed the molecular imprinting electrochemical sensor for the determination of L-Tryptophan. The MIP was fabricated by the polymerization reaction of ethyl silicate (TEOS), phenyltrimethoxysilane (PTMOS) and phenyltrimethoxysilane (MTMOS). The presence and removal of the template molecule L-Tryptophan in the MIP film were confirmed by cyclic voltammetry. We optimized for the conditions of Sol-gel preparation, the removal time of template, the conditions of the template molecule selective enrichment and the pH of solvent. The sensor showed an excellent selectivity and a high sensitivity for L-Tryptophan detection, with a linear range form 1.0×10^-9 to 1.0×10^-5 mol/L (r = 0.9958) and a limit of detection as low as 1.0×10^-12 mol/L. The sensor was successfully applied to the determination L-Tryptophan in the serum samples.3. Constructed the MWNTs/PVA/(pq)₂Ir(N-phMA) modified electrode. The first time prepared the ECL-MIP sensor which is the second modification of sol-gel molecular imprinting film on the MWNTs/PVA/(pq)₂Ir(N-phMA) modidied electrode surface. The study is based carbon nanotubes dispersion in the solution with polyvinyl alcohol as the dispersant. L-Tryptophan as coreactant, optimized for the amount of MWNTs and (pq)₂Ir(N-phMA), while the pH of solvent. An MIP -ECL sensor coated with a (Mints/PVA/(pq)₂Ir(N-phMA) modified layer and a thin molecularly imprinted sol-gel film has been developed for the determination of L-Tryptophan in the liquid phase. A solid state ECL sensor was fabricated by incorporation of the iridium complex with multiwalled carbon nanotubes (MWNTs) and poly (vinyl alcohol) (PVA) to form a dispersion solution, and then the mixture was directly deposited onto the surface of a glass carbon (GC) electrode. An MIP film was developed by using a sol-gel with a template molecular. The affinity of L-Tryptophan to the imprinted film was determined by cyclic voltammetry. We optimized for the pH of the buffer solution, molecularly imprinted polymers by the amount of enrichment time and acidity, the removal time of template. The sensor showed an excellent selectivity and a high sensitivity for L-Tryptophan detection. The sensor responses linearly to L-Trp from 5.0×10^-14 to 1.0×10^-10 mol/L (r² = 0.9917) and a limit of detection as low as 1.0×10^-16 mol/L. The sensor was successfully applied to the determination L-Tryptophan in the serum samples.4. Explored the ionic liquids and tris (2-phenylpyridine) iridum complexes Ir (ppy)3in ECL application. Constructed the ionic liquid/ Ir (ppy)₃modified electrode. We optimized for the amount of ionic liquid and Ir(ppy)₃, the pH of solvent. The sensor showed an excellent sensitivity for L-Tryptophan detection.