School of Environmental and Chemical Engineering , Shanghai University , Shanghai , China 200444.
School of Life Sciences , Shanghai University , Shanghai , China 200444.
ACS Nano. 2019 Sep 24;13(9):10405-10418. doi: 10.1021/acsnano.9b04200. Epub 2019 Aug 26.
Photodynamic therapy (PDT) has been considered as a promising and noninvasive strategy for clinical cancer treatment. Nonetheless, building a smart "off-on" theranostic PDT platform to spatiotemporally control the generation of reactive oxygen species in the PDT treatment still remains challenging. Here, we have rationally developed photoswitching upconversion nanoparticles (UCNPs) with orthogonal emissive properties in response to two distinct near-infrared (NIR) emissions at 808 and 980 nm, , red emission with 980 nm excitation and green emission with 808 nm excitation. Unlike traditional photoswitching UCNPs, these specially designed core-shell-shell structured UCNPs do not require complicated multilayer doping as their red and green upconversion luminescence both originate from the same activator Er ions in the core structure. As a proof of concept, we have demonstrated the capability of these orthogonal emissive UCNPs for imaging-guided PDT in a real-time manner, where the red emission excited by 980 nm light is used to trigger PDT and the green emission with 808 nm excitation is to diagnose and monitor the therapeutic treatment. Our study suggests that such specially designed UCNPs with orthogonal emissions hold great promise for NIR light-targeted and imaging-guided therapy under precisely spatiotemporal control.
光动力疗法（PDT）已被认为是一种有前途的、非侵入性的临床癌症治疗策略。然而，构建一种智能的“开-关”治疗性 PDT 平台，以时空控制 PDT 治疗中活性氧的产生仍然具有挑战性。在这里，我们合理地开发了具有正交发射特性的光开关上转换纳米粒子（UCNPs），以响应两个不同的近红外（NIR）发射，分别为 808nm 和 980nm， ，980nm 激发的红光发射和 808nm 激发的绿光发射。与传统的光开关 UCNPs 不同，这些专门设计的核壳壳结构 UCNPs 不需要复杂的多层掺杂，因为它们的红光和绿光上转换发光都源自核心结构中的相同激活剂 Er 离子。作为概念验证，我们展示了这些正交发射 UCNPs 在实时成像引导 PDT 中的能力，其中 980nm 光激发的红光用于触发 PDT，而 808nm 激发的绿光用于诊断和监测治疗。我们的研究表明，这种具有正交发射的专门设计的 UCNPs 在精确的时空控制下具有很大的潜力用于近红外光靶向和成像引导治疗。
