Synthesis Of New Near-infrared Nano, Micron Fluorescent Probes And Its Recogition And Sensing To Heavy Metal Ions

Chapter 1:The characteristics of gold nanomaterials are depicted in brief. The synthetic methods, the characterization techniques for gold nanoparticles and their application in detection of metal ion were reviewed in detail in this chapter. According to these reviews, our own research content and innovative were put forward.Chapter 2:GSH-AuNPs and Au38(SC2H4Ph)24 gold nanoparticles protected with GSH and PhCH2CH2SH as ligands have been synthesized, in which HAuCl4·3H2O was reduced by NaBH4 under different condition. GSH-AuNPs and Au38(SC2H4Ph)24 are water-soluble and insoluble respectively. Both nanoparticles are stable and have dark brown color. Their size and properties were characterizated by fluorescence spectra, UV-visible absorption, FTIR, HNMR and Transmission Electron Microscope (TEM).Chapter 3:The selective recognition of GSH-AuPNs nanoparticles to metal ions including sixteen kinds of metal ions were studied based on fluorescence titrations. The gold nanoparticles have maximum fluorescence emission peak in near infrared region. The pH has weak influence on fluorescence intensity of gold nanoparticles. The fluorescence of GSH-AuPNs nanoparticles was found to have some extent quenching after added to three kinds of metal ions(Cu2+,Hg2+, Pb2+), especially for Cu2+. With the optimum conditions desceibed, The linear range was from 2.5×10-6 to 1.0×10-5. The limit of detection is 1.1×10-7 (S/N=3). The proposed method exhibits good repeatability and selectivity.Chapter 4:Porphyrin micronparticles were preparated by solvent replacement method, and the kinds of infuence infactors of preparation including the kinds and the ratio of organic solvent and the kinds and concentration of surfactant were exploring. The morphology and size distribution of porphyrin micronparticles were characterized by microscope and size distribution instrument. The results show that the different organic solvent and different ratio prepared different size of the porphyrin micronparticles. The porphyrin micronparticles has well reproducibility in THF. Moreover, in the same concentration of surfactant, the size of porphyrin micronparticles is that the largest is in anionic surfactant solution and the most little is in cationic surfactant solution. The distribution of particle size exists two states in soultion of triton-x-100 in different concentration:the particle size is 6μm when the concentration of surfactant is higher than critical micelle concentration(CMC); on the contrary, when the concentration of surfactant is lower than CMC, the particle size is 0.5μm. The solublity of porphyrin has been changed and its biological activity has been strengthened through solvent replacement method. Therefore, the application of water-soluble porphyrin microparticles has been extended, which can be expected to be applied in reaction with biological molecules.