Facile synthesis of hollow microspherical YPO 4 : Eu 3+ /Tb 3+ using polystyrene spheres as sacrificial template and its photoluminescent properties

Micro & nano letters

article

Yu Gao¹  Jinzhao Feng²  Feixue Ai¹  Guiyan Zhao¹  Yanfeng Bi¹  Fu Ding²  Yaguang Sun²  Zhenhe Xu² 

[1] College of Chemistry, Chemical Engineering and Environmental Engineering, Liaoning Shihua University;The Key Laboratory of Inorganic Molecule-Based Chemistry of Liaoning Province, College of Applied Chemistry, Shenyang University of Chemical Technology

关键词: yttrium compounds;    europium;    terbium;    photoluminescence;    precipitation (physical chemistry);    ion exchange;    calcination;    doping;    transmission electron microscopy;    scanning electron microscopy;    thermal analysis;    Fourier transform infrared spectra;    X-ray diffraction;    polystyrene spheres;    sacrificial template;    photoluminescent properties;    monodisperse hollow microspherical material;    convenient homogeneous precipitation method;    ion exchange method;    calcination;    X-ray diffraction;    Fourier transform infrared spectra;    thermogravimetric analysis;    scanning electron microscopy;    transmission electron microscopy;    ultraviolet excitation;    doped microspherical material;    YPO4Eu;    YPO4Tb;   

DOI  :  10.1049/mnl.2017.0398

学科分类：计算机科学（综合）

来源: Wiley

【 摘 要 】

The cancer therapeutic strategies known to date are not adequate for all cancer patients. Most of them are followed by a high rate of side effects and complications. The L-tryptophan depletion bioreactor is described as a possible new method of cancer therapy. L-tryptophan is an essential am i no acid which has been recognized as an important cancer nutrient and its removal can lead to destruction of the tumour. Normal human cells or tumor cells cannot synthesize L-tryptophan and therefore tumor resistance is unlikely to develop. L-tryptophan is also a constituent for different bio-molecules such as Serotonin, Melatonin, and is needed for other synthesis processes in the cell growth. L-tryptophan degrading enzymes with 3 iso-enzymes called tryptophan side chain oxydase (TSO) I, II, III were isolated. The 3 iso-enzymes can be differentiated by tryptic digestion. They have different molecular weights with different effectivenesses. All the TSO enzymes have heme that can catalyze essentially similar reactions involving L-tryptophan as a substrate. The most effective TSO is the type TSO III. A column which contained TSO as a bioreactor was integrated in a plasmapheresis unit and tested it in different animals. In sheep and rabbits L-tryptophan depletion in plasma was shown at 95% and 100% rates respectively by a single pass through the bioreactor. The results in immune supprimized rats with tumors were impressive, too. In 20 different tumor cell lines there were different efficacies. Brest cancer and medulloblastoma showed the greatest efficacy of L-tryptophan degrading. The gene technology of TSO production from Pseudomonas is associated with formation of endotoxins. This disadvantage can be prevented by different washing procedures or by using fungal sources for the TSO production. TSO III is developed to treat cancer diseases successfully, and has low side effects. A combination of L-tryptophan depletion with all available cancer therapies is possible.

【 授权许可】

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