Synthesis Of Cationic/Luminescent Polymer Nanoparticles And Their Interaction With Biomacromolecules

Cationic copolymer nanoparticles have attracted the researchers' attention, due to the ability to interact efficiently with other substances like textile, pollutants in sewage water, biomacromolecules and so on. Cationic luminescent copolymer nanoparticles combine the advantages of cationic substance and luminescent materials, making themselves possess great potential application in the biomedical fields, as drug delivery systems, gene vectors, protein speration and bioprobes and so on. The work presented here mainly focus on the following contents:Firstly, cationic copolymer nanoparticles were prepared by emulsifier-free emulsion polymerization of styrene (St) and n-butyl acrylate (BA), using [2-(methacryoyloxy ethyl] trimethylammonium chloride (DMC) as the cationic functional comonomer and 2,2'-azobis (2-methypropionamidine) as the cationic initiator. FT-IR spectroscopy,1H-NMR spectroscopy and GPC were applied to characterize the chemical structure and molecular weight of the obtained copolymer. The size and size distribution of the nanoparticles were characterized through photon correlation spectroscopy (PCS). The interaction of nanoparticles with bovine serum albumin (BSA) was investigated by the means of TEM, zata potential and fluorescence spectroscopy. It was found that the copolymer nanoparticles were monodisperse spheres with the diameter less than 90nm and clean surface, and can complex well with BSA through electrostatic interaction.Secondly, polymerizable rare earth complex Eu(AA)3Phen was synthesized by complexion of europium ion, acrylic acid (AA), and 1,10-phenanthroline (Phen). The structure and fluorescence properties of the complex were studied by elemental analysis,1H-NMR spectroscopy, and fluorescence spectroscopy. Eu-containing copolymer poly(PEGMA-co-MMA-co-DMC-co-Eu(AA)3Phen) (PPMDEu) was then synthesized by free radical copolymerization of Eu(AA)3Phen and other functional monomers including poly(ethylene glycol) methyl ether methacrylate (PEGMA) and [2-(Methacryloyloxy) ethyl] trimethylammonium chloride (DMC).1H-NMR spectroscopy and fluorescence spectroscopy were used to characterize the copolymer and the interactions between the copolymer and DNA was investigated by TEM, fluorescence spectroscopy, and agarose gel electrophoresis. The desired luminescent cationic copolymer was successfully obtained. The copolymer can form micelles in water solution and can efficiently bind to DNA molecules through electrostatic interaction. The results suggest the potential use of PPMDEu in bioprobes and gene vectors.