School of Physics, State Key Laboratory of Optoelectronic Materials and Technologies, Sun Yat-sen University, Guangzhou 510275, People's Republic of China.
School of Physics and Electronic Engineering, Zhengzhou Normal University, Zhengzhou 450044, People's Republic of China.
Nanotechnology. 2021 Aug 2;32(43). doi: 10.1088/1361-6528/ac12ed.
High-sensitivity optical imaging can be achieved through improving upconversion photoluminescence (UCPL) efficiency of localized surface plasmon resonance (LSPR)-enhanced excitation and emission. Herein, we report a type of UCPL nanoprobe, Au nanospheres assemblage@GdO:Yb/Ln(Ln = Er, Ho, Tm), which exhibits emission enhancements from 46- to 96-fold as compared with its Au-free counterparts. The aggregation and interaction among Au nanospheres embedded inside the nanoprobe brings about three characteristic LSPR peaks in visible and near-infrared regions according to simulated and experimental absorption spectra, resulting in both excitation and emission fields simultaneously intensified all through the entire nanoprobe. We addressed a characteristic wavelength dependence on emission amplifications, which could be elucidated by a LSPR-enhanced UCPL mechanism and relevant rate equations that we addressed. The nanoprobe was verified to have a superior capability for optical bio-imaging with a negligible toxicityand. This study realizes a synchronous double-field-enhanced upconversion of optical nanoprobe, and may gain an insight into its mechanism underlying for LSPR-induced UCPL enhancement.
通过提高局域表面等离子体共振（LSPR）增强激发和发射的上转换光致发光（UCPL）效率，可以实现高灵敏度光学成像。在此，我们报告了一种 UCPL 纳米探针，Au 纳米球组装体@GdO:Yb/Ln（Ln=Er，Ho，Tm），与无 Au 对应物相比，其发射增强了 46 至 96 倍。纳米探针内部嵌入的 Au 纳米球的聚集和相互作用根据模拟和实验吸收光谱产生了三个可见和近红外区域的特征 LSPR 峰，从而使整个纳米探针同时同时增强了激发和发射场。我们解决了发射放大的特征波长依赖性，这可以通过我们解决的 LSPR 增强 UCPL 机制和相关速率方程来阐明。该纳米探针具有优异的光学生物成像能力，毒性可忽略不计。这项研究实现了光学纳米探针的同步双场增强上转换，并且可以深入了解其 LSPR 诱导的 UCPL 增强的机制。
