Design And Synthesis Of Water Soluble Conjugated Polyelectrolytes Containing Metalloporphyrin Complexes For Biological Applications

Water-soluble conjugated polymers(WSCPs)are generally composed of ?-conjugated backbones which determining the main optical properties and charged side-chains which determining water solubility.WSCPs have many advantages in biomedicine,such as high brightness,large extinction coefficients,superior photostability,low cytotoxicity,stability and versatile surface modification.Metalloporphyrins are one of the cornerstones on the existence of life,and have ubiquitous biological functions in nature.They are widely used in the fields of biosensing,fluorescence imaging,medicine and photodynamic therapy.In this thesis,a kind of WSCPs containing metalloporphyrin was synthesized by combining the advantages of WSCPs and metalloporphyrin,and its application in cell imaging,magnetic resonance imaging(MRI)and photodynamic therapy(PDT)was studied.1.By introducing the T1-enhanced manganese porphyrin into the conjugated polymer of poly(fluorene),a polyelectrolyte with dual mode imaging function has been synthesized.The approximately 100 nm spherical nanoparticles are formed in the PBS buffer solution via self-assembly caused by amphiphilic chemical structure.Their photophysical properties are characterized by UV-visible absorption and fluorescence spectroscopy,and the morphology are characterized by transmission electron microscopy(TEM)and dynamic light scattering(DLS).The results show conjugated polymer nanoparticles as-prepared have strong absorption,high fluorescence quantum yield,good stability,excellent biocompatibility,cell imaging and high relaxivity values.These results indicate that it has a wide application prospect in living cell imaging and MRI.2.A kind of novel conjugated polymer containing porphyrin palladium has been designed and synthesized.By using the amphiphilic molecular structure,the nanoparticles are formed about 30 nm by self-assembly in aqueous solution.The structures of intermediates and target polymer are characterized by nuclear magnetic resonance(NMR)and gel permeation chromatography(GPC).The morphology of the polymer is studied by TEM and DLS.The experimental results show that the nanoparticles have uniform particle size,good dispersibility and stability,and can be used for cell imaging.It is important that the singlet oxygen can be produced efficiently under the condition of illumination,and further causes the apoptosis of tumor cells.Therefore,we design the water-soluble conjugated polymer nanoparticles to achieve the purpose of cell imaging and photodynamic therapy.