Construction And Study Of Electrochemiluminescence Or Photoelectrochemical Biosensors Based On Titanium Dioxide And Noble Metal

Nano-materials are known as "the 21 st century's most promising materials". Information technology, biotechnology and nano-materials have become the three pillars of social and economic development and the strategic high ground in the 21 st century. Nanomaterials have unique physical and chemical properties, such as small size effect, large specific surface area, high reactivity, quantum effects. With the rapid development of nanotechnology, today, the research of nano-materials is no longer confined to the basic exploration and simple synthesis, but puts a lot of nano-materials into a variety of practical applications according to their characteristics, and services for people's work and life. In recent years, nano-materials have been widely used in sensors, and achieved obvious results. Nano-biosensors with strong adsorption, good sensitivity and high selectivity, are widely used in clinical, food, environmental, military and other fields, and get more and more attention.Based on noble metal nanoparticles and titanium dioxide nanomaterial, using electrochemiluminescence and photoelectrochemical technology, we commited to ourselves design and build new immunosensor. Nanoparticles and nanostructured materials were used to amplify the immune-detection signal and increased immune-cell sensitivity. Good performance of photovoltaic materials was integrated fully, to increase the sensitivity and selectivity of biosensors. At the same time, biosensors possessed better detection efficiency, higher degree of automation. There were following studies around the main topic:1. Designed an electrochemiluminescence immunosensor, based on electrode modified with platinum-graphene-carbon nanotube composites, and secondary antibody modified with carbon dots-platinum/iron alloy composite nano-materials. The immunosensor took full advantage of large surface area of graphene-carbon nanotube composites and platinum/iron alloy to amplify the signal, and took full use of good optical properties of carbon dots;2. Designed an electrochemiluminescence immunosensor, based on ITO glass modified with gold-palladium nanoparticles, and secondary antibodies modified with three dimensional flower-like titanium dioxide. To amplify optical signals, took advantage of the good conductivity and big volume-surface area of Au-Pd nanoparticles. Three dimensional flower-like titanium dioxide loading more secondary antibodies could achieve double amplification;3. FTO glass modified with pinnate titanium dioxide, connected with carbon nanotube-gold through aptamer. Due to the resonance energy transfer, produced faint light current after irradiation of light. After joined in the target of carcinoembryonic antigen, CEA specific binded with aptamer, undermined the resonance energy transfer, enhanced photocurrent, amplified optical signal.