Conductive Polymer Nanoparticles And Their Analytical Application

Conductive polymers are excellent new functional materials. They have obvious polymer characteristics, such as good flexibility, plasticity and are easy to mold. They also have unique optical, electrical, magnetic, thermal and other properties. So conductive polymers have been used in sensors and molecular devices, electromagnetic shielding, metal corrosion, electrochemical, bio-technology and other fields.Nano-material is one kind of a material which size is nanometer scale range (1-100 nm) at least in one dimension of three-dimensions. In recent years, conducting polymer nanoparticles with regular morphology and large surface area have been received much attention duo to their widely applications in catalysis, separation, drug delivery and sensors. Compared to other conductive polymer nanoparticles, polypyrrole nanoparticles have excellent environmental stability and biocompatibility as chemical and biological sensors materials in a more broad application potential. Thus the use of the functional polypyrrole, polypyrrole complex films or nanoparticles, for a load or a fixed biological material in the electrochemical biosensor has become a hot topic in recent research.The electrogenerated chemiluminescence (ECL) sensors and biosensors have been received much attention duo to their high sensitivity, good selectivity, fastness and simplicity.This thesis aims to synthesize novel conductive polymer nanoparticles and to develop a ECL biosensor using synthesize conductive polymer. This thesis consists of four chapters. The first chapter is introduction, in which the synthesis, the structure and characteristics of conductive polymers are described, and the application of them, and especially includes the conductive polymer nanometer material's application in the electrochemical sensors are reviewed.The second chapter is the research of synthesis poly (pyrrole-co-pyrrole propylic acid) nanoparticles. Poly (pyrrole-co-pyrrole propylic acid) nanoparticles (PPy/PPa NPs) were synthesized by using an oil/water micro-emulsion method. The PPy/PPa NPs synthesized were characterized by fourier transform infrared absorption spectroscopy (FTIR), transmission electron microscope (TEM) and scanning electron microscope (SEM). The nanoparticles have a more regular morphology, and particle size at 40-50 nm. And the presence of the carboxylic acid (-COOH) functionality in nanoparticles was confirmed using the FTIR.In the third chapter, an ECL sensor for the determination of tri-propylamine (TPA) was designed and fabricated by coating Rul complex-PPy/PPa NPs on the surface of a paraffin-impregnated graphite electrode (PIGE). It was found that ECL intensity of the sensor fabricated was linear with the concentration of TPA in the range from 1.0×10-7 to 1.0×10-5 mol/L, with a detection limit of 3×10-8 mol/L TPA(S/N=3). The ECL sensor also showed good reproducibility and stability.In the forth chapter, an ultrasensitive ECL detection method of thrombin based on PPy/PPa NPs carrying a large number of ruthenium complex tags was developed. The probe single thrombin aptamer II and ruthenium complex were loaded on PPy/PPa NPs which was taken as an ECL probe. When the capture thrombin aptamer I with an amine group was covalently immobilized onto the surface of the PIGE, and then recognition of the target thrombin and further captured with the ECL probe to form DNA sandwich conjugate, a strong ECL response was electrochemically generated. The ECL intensity was linearly related to the concentration of thrombin in the range from 1.0×10-15 to 1.0×10-12mol/L(S/N=3).