School of Nano-Tech and Nano-Bionics, University of Science and Technology of China, Hefei 230026, China.
CAS Key Laboratory of Nano-Bio Interface, Division of Nanobiomedicine and i-Lab, Suzhou Institute of Nano-Tech and Nano-Bionics, Chinese Academy of Sciences, Suzhou 215123, China.
Nano Lett. 2021 Aug 11;21(15):6576-6583. doi: 10.1021/acs.nanolett.1c01962. Epub 2021 Jul 24.
Rational design of efficient lanthanide-doped down-shifting nanoparticles (DSNPs) has attracted tremendous attention. However, energy loss was inevitable in the multiple Ln doping systems owing to complex energy migration processes. Here, an efficient NaErF@NaYF@NaYF:10%Nd@NaYF DSNP was tactfully designed, in which a buffer layer of NaYF was modulated to restrict the interionic energy migration between Er and Nd; meanwhile, the surface defects were passivated by an outermost layer of NaYF. Therefore, the as-prepared DSNPs exhibited two intensive near-infrared-II fluorescence emissions of 1525 nm from Er and 1060 nm from doped Nd under 808 nm excitation. Further, a novel ratiometric nanoprobe NaErF@NaYF@NaYF:10%Nd@NaYF@A1094 was fabricated by coupling an organic dye of A1094 onto the DSNP surface to quench the 1060 nm emission by the efficient Förster resonance energy transfer, while emission at 1525 nm retained. Thereafter, these activatable ratiometric nanoprobes were used for rapid and sensitive detection of peroxynitrite (ONOO) in vivo.
高效镧系掺杂下转换纳米粒子（DSNP）的合理设计引起了极大关注。然而，由于复杂的能量迁移过程，在多镧系掺杂体系中能量损失是不可避免的。在这里，巧妙地设计了一种高效的 NaErF@NaYF@NaYF:10%Nd@NaYF DSNP，其中调制了 NaYF 缓冲层以限制 Er 和 Nd 之间的离子间能量迁移；同时，最外层的 NaYF 钝化了表面缺陷。因此，所制备的 DSNP 在 808nm 激发下表现出两个强烈的近红外-II 荧光发射，分别来自 Er 的 1525nm 和掺杂 Nd 的 1060nm。此外，通过将有机染料 A1094 偶联到 DSNP 表面，制备了一种新型的比率型纳米探针 NaErF@NaYF@NaYF:10%Nd@NaYF@A1094，通过有效的Förster 共振能量转移来猝灭 1060nm 发射，同时保留 1525nm 发射。此后，这些激活的比率型纳米探针用于体内快速和灵敏地检测过氧亚硝酸盐（ONOO）。
