Continuous hydrothermal synthesis of surface-functionalised nanophosphors for biological imaging
Continuous hydrothermal synthesis of surface-functionalised nanophosphors for biological imaging
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DOI：
10.1039/c2ra21798h
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发表时间：
2012-10
期刊：
影响因子：
3.9
通讯作者：
R. Gruar;C. Tighe;J. Muir;J. Kittler;Maciej Wodjak;A. Kenyon;J. Darr
中科院分区：
文献类型：
--
作者：
R. Gruar;C. Tighe;J. Muir;J. Kittler;Maciej Wodjak;A. Kenyon;J. Darr
使用纳米颗粒前体（相应的掺杂的羟基氧化物的晶体）的快速热处理制备平均粒度为35 nm的结晶且高度发光的纳米颗粒红色磷光体（在Y2 O3中标称4mol%Eu）。纳米颗粒前体（其也在来自铕中的5D 0 → 7 F2跃迁的宽UV激发下在600-630 nm区域上显示出强的红色发射）使用在约200 nm下操作的连续水热过程（利用超临界水）在单个步骤中制备。380 °C和24.1 MPa。对选定的热处理纳米材料进行光致发光（PL）和时间分辨PL测量，并显示出>2.25 ms的显著延长的寿命（本体材料通常约为2.25 ms）。1.7 ms）。作为增加热处理时间的函数的发射寿命的增加归因于粒子间效应。制备表面官能化的纳米颗粒，并进一步评估其作为生物成像的探针，其中初始前体磷光体和高度发光的氧化物变体都在细胞成像研究中在470 nm的激发下，使用以640 nm为中心的宽带通滤波器被清楚地分辨。因此，本文所用的方法有希望得到用于发光安全油墨和作为生物成像探针的容易配制的稳定胶体。
A crystalline and highly luminescent nanoparticle red phosphor with average particle size of 35 nm (nominal 4 mol% Eu in Y2O3) was prepared using flash heat-treatment of a nanoparticle precursor (crystals of the corresponding doped oxyhydroxide). The nanoparticle precursors (which also show strong red emission over the 600–630 nm region under broad UV excitation from transitions of 5D0 → 7F2 in europium) were prepared in a single step using a continuous hydrothermal process (utilising supercritical water) operated at ca. 380 °C and 24.1 MPa. Photoluminescence (PL) and time-resolved PL measurements were performed on selected heat-treated nanomaterials and revealed a significantly extended lifetime of >2.25 ms (bulk material typically ca. 1.7 ms). Increases in the emission lifetime as a function of increased heat-treatment time were attributed to inter-particle effects. Surface-functionalized nanoparticles were prepared and further evaluated as probes for biological imaging with the initial precursor phosphor and the highly luminescent oxide variant both being clearly resolved in cell imaging studies under an excitation of 470 nm, using a wide pass band filter centered at 640 nm. Thus, the method employed herein holds promise for readily formulated stable colloids for luminescent security inks and as biological imaging probes.