Preparation Of Fluorene Based Copolymer Nanoparticles And Its Application In Fluorescence Probes

Organic optoelectronic material is a research hotspot in the field of photoelectricmaterial. Conjugated polymer material is a sort of considerable organic optoelectronicmaterials. As one kind of conjugated polymers, fluorene-based polymers are widelyused in various traditional fields, such as, light-emitting diodes, field effect transistors,solar cells, high-emitting electrochemical cells and so on. In addition, compared withtraditional fluorene-based polymer materials, the nano-material of fluorenn-basedpolymer not only has excellent photoelectric properties, but also has thecharacteristics of nano-materials. Thus, the nano-material of fluorene-based polymershows promising applications in bio-imaging, PH and temperature sensing. Recently,a facile reprecipitation or mini-emulsion polymerization method for preparation of avariety of conjugated polymer nanoparticles was reported. In this method, an organiccompound is first dissolved in a hydrophilic organic solvent (e.g. THF), and thissolution is injected into water, which acts as a poor solvent, leading to the formationof a nanoparticles dispersion. The nanoparticles prepared by this way have smallparticle size, perfect chemical stability and monodispersity. This method couldprepare polymer nanoparticles rapidly and simply, so it opened up a wide prospectfor application of polymer nanoparticles.This paper mainly explored the preparation of mono-disperse nanoparticles offluorene-based polymer and the application in fluorescent probe, and elucidated intwo sections. In the first section, a simple and convenient method was selected toprepare the fluorene-based copolymer nanoparticles. And the size of the nanoparticles(1-3nm) is far smaller than that currently reported in the literature. What’s more, theauthor realized photoluminescence regulation to the nanoparticles that preparedthrough the method of controlling the concentration of fluorene-based copolymer solution, and came to the conclusion: as a result of the differences in theβ-phasecontent of every polyfluorene unit and the mode of energy transfer among the nanoparticles in different concentrations, the author realized the photoluminescenceregulation to the fluorene-based copolymer nanoparticles by changing theconcentration of the fluorene-based copolymer solutions.In the second section, the paper mainly studied the feasibility of the twofluorene-based copolymers as Fe3+fluorescent probe. In this section, to determinedifferent sorts of metal cations using two kinds of fluorene-based polymers with etherchain, evident fluorescence quenching effects were discovered from Fe3+to the twokinds of fluorene-based polymers with ether chain. And the fluorescence quenchingeffects were proved to be dynamic-static quenching in the means of fluorescencespectra analysis. In addition, through exploration to the optimal detectingconcentration to Fe3+and the detection to the limitation of fluorescence probe, thedetecting extremity to Fe3+and its maximum fluorescence quenching coefficient ofthe two kinds of fluorene-based polymers with ether chain was obtained. Via the studyof this section, the author draw a conclusion that the two kinds of fluorene-basedpolymers with ether chain are splendid Fe3+fluorescence probes, and they have thecharacters of high selectivity, high sensitivity and low consumption.