Preparation Of Optical Functional Nanomaterials And Research Of Their Drug Release Profile

In modern material chemistry and biomedicine,well defined morphologies and accuratelytunable sizes of nanomaterials has been taken extensively attention. Above all, the research ofrare-earth upconverting luminescent nanoparticles is more important. They have manyadvantages, such as low toxicity, high chemical stability, sharp emission line, long emissionlifetime. Additionally, NIR excitation under continuous-wave(cw) at980nm makes manyadvantage, too, such as deeper light-penetration depth, no photodamage to living organismsand avoid background fluorescence effectively. All these useful properties have illuminatedthat UCNPs have great potential to be a new kind of biological luminescent labels.There are two parts in this dissertation: one is the preparation of downconvertingluminescent materials, using Pechini-type sol-gel method by vacuum nano-casting route aswell as the application of the materials in drug release and uptake process. The other is thepreparation of upconverting luminescent materials using thermal solvethermal methodologyand the surface modification of these nanoparticles.1. By vacuum nano-casting route CaWO4:Tb3+@SiO2nanocapsules have been preparedusing simple and environmentally frendly sol-gel and sacrificial template. The release profileof CaWO4:Tb3+@SiO2nanocapsules at different pH values as well as the increase of emissionintensity of the nanocapsules with the release of DOX are researched. Meanwhile, The rapidcancer cell uptake process also display good biocompatibility of CaWO4:Tb3+@SiO2nanocapsules.2. UCNPs β-NaYF4:Yb3+/Er3+nanoparticles are prepared by thermal solvothermalmethodology in oleic acid/octadecylene/NaF reaction system. The β-NaYF4:Yb3+/Er3+nanoparticles are capped with gelatine to modify surface properties at ultrasonic. Aftersurface modification, β-NaYF4:Yb3+/Er3+nanoparticles as synthesized are well dispersed andthe UC emission is still bright.