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利用St ber法和交联法制备出具有荧光和磁性功能的Fe3O4/SiO2/CMCH/CdTe微球,并对其性能和应用效果进行了分析讨论.首先以正硅酸四乙酯为前躯体,Fe2+和Fe3+物质的量的比为1∶2,利用超临界干燥法制备出了Fe3O4/SiO2复合微球;并通过透射电镜对其进行观察,Fe3O4颗粒粒径为10 nm,SiO2层厚度为5 nm;其次羧甲基化的壳聚糖(CMCH)被嫁接在Fe3O4/SiO2表面上;然后利用水热法制备出CdTe荧光颗粒,通过壳聚糖与CdTe之间的静电吸引作用,CdTe被吸附在壳聚糖表面;最后利用戊二醛对壳聚糖的选择性交联作用制备出粒径在200 nm以内,饱和磁化强度为22.16 A.m2/kg,且具有良好荧光性能的Fe3O4/SiO2/CMCH/CdTe微球.荧光光谱分析表明最大发射波长从519 nm红移到528 nm,也证实了荧光颗粒CdTe成功吸附在Fe3O4/SiO2/CMCH表面.在动物实验中,该复合微球也显示出良好的荧光性、磁性及稳定性.
The Fe3O4 / SiO2 / CMCH / CdTe microspheres with fluorescence and magnetic properties were prepared by the St ber method and the cross-linking method, and their properties and application effects were analyzed and discussed.First, tetraethyl orthosilicate as a precursor, The Fe3O4 / SiO2 composite microspheres were prepared by supercritical drying. The size of Fe3O4 particles was 10 nm and the thickness of SiO2 layer was 5 nm. Secondly, carboxymethylated chitosan (CMCH) was grafted onto the surface of Fe3O4 / SiO2. CdTe fluorescent particles were prepared by hydrothermal method. CdTe was adsorbed by the electrostatic attraction between chitosan and CdTe Finally, the surface of chitosan was prepared by the selective crosslinking of glutaraldehyde with glutaraldehyde. The results showed that the saturation magnetization was 22.16 A.m2 / kg with a diameter of less than 200 nm and a good fluorescence of Fe3O4 / SiO2 / CMCH / CdTe microspheres.Fluorescence spectroscopy analysis showed that the maximum emission wavelength was red-shifted from 519 nm to 528 nm, and it was also confirmed that the fluorescent CdTe particles were successfully adsorbed on the surface of Fe3O4 / SiO2 / CMCH.In animal experiments, the composite microspheres also showed Good fluorescence, magnetic and stability.