Luminescent rare earth nanoparticles exhibit superior optical stability over commonly‐used organic dyes and higher biocompatibility over quantum dots, rendering them advantageous as bioimaging nanoprobes. However, their typical excitation inhibits their broad employment with conventional fluorescence microscopes and, thus, solutions are sought to shift their activation in the long‐wavelength (near‐UV) spectral region. Here, we synthesize YVO₄:Eu³⁺ nanophosphors by flame aerosol technology to systematically study the effect of Bi³⁺ codoping on their luminescence. That way, we identify an optimal Bi‐content for sufficient near‐UV activation. These nanophosphors are highly crystalline and appeared bright red under a conventional fluorescence microscope, facilitating bioimaging with HeLa cells and in vitro dosimetry correlations in the presence and absence of serum. The nanophosphor superiority over organic‐dye‐labeled silica nanoparticles is shown during dynamic imaging for 4 h without photobleaching for the former. These YVO₄:Eu³⁺/Bi³⁺ nanophosphors can provide a non‐photobleaching tool for further dynamic nanoparticle‐cell interaction studies with conventional fluorescence microscopes. © 2018 American Institute of Chemical Engineers AIChE J, 64: 2947–2957, 2018

中文翻译：

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近紫外线激活的，光稳定的纳米荧光粉，用于体外剂量测定和动态生物成像

发光稀土纳米粒子具有优于常用有机染料的光学稳定性，并具有优于量子点的生物相容性，使其作为生物成像纳米探针具有优势。然而，它们的典型激发阻碍了它们在常规荧光显微镜下的广泛应用，因此，寻求解决方案以在长波长（近紫外）光谱区域中转移它们的活化作用。在这里，我们通过火焰气溶胶技术合成了YVO ₄：Eu ³⁺纳米荧光粉，系统地研究了Bi ³⁺的作用。共掺杂它们的发光。这样，我们确定了最佳的Bi含量，足以进行近紫外光活化。这些纳米荧光粉具有高度结晶性，在常规荧光显微镜下呈亮红色，有助于在存在和不存在血清的情况下对HeLa细胞进行生物成像，并实现了剂量学相关性。在动态成像过程中显示4个小时后，纳米磷光剂优于有机染料标记的二氧化硅纳米颗粒，而前者未进行光漂白。这些YVO ₄：Eu ³⁺ / Bi ³⁺纳米磷光剂可提供一种非光漂白工具，用于使用常规荧光显微镜进行进一步的动态纳米粒子-细胞相互作用研究。©2018美国化学工程师学会AIChE J，64：2947–2957，2018