Ministry of Education Key Laboratory for the Synthesis and Application of Organic Functional Molecules and College of Chemistry and Chemical Engineering, Hubei University, Wuhan, 430062, China.
Key Laboratory of Analytical Chemistry for Biology and Medicine (Ministry of Education), College of Chemistry and Molecular Sciences, Wuhan University, Wuhan, 430072, China.
Small. 2020 Jan;16(1):e1905084. doi: 10.1002/smll.201905084. Epub 2019 Nov 29.
Lanthanide-doped upconversion nanoparticles (UCNPs) can convert two or more lower-energy near-infrared photons to a single photon with higher energy, which makes them particularly suitable for constructing nanoprobes with large imaging depth and minimal interference of autofluorescence and light scattering from biosamples. Furthermore, they feature excellent photostability, sharp and narrow emissions, and large anti-Stokes shift, which confer them the capability of long-period bioimaging and real-time tracking. In recent years, UCNPs-based nanoprobes (UC-nanoprobes) have been attracting increasing interest in biological and medical research. Signal contrast, the ratio of signal intensity after and before the reaction of the probe and target, is the determinant factor of the sensitivity of all reaction-based probes. This progress report presents the methods of constructing UC-nanoprobes, with a focus fixed on recent strategies to improve the signal contrast, which have kept on promoting the bioapplication of this type of probe.
镧系掺杂上转换纳米粒子（UCNPs）可以将两个或更多低能量近红外光子转换为具有更高能量的单个光子，这使得它们特别适合构建具有大成像深度、最小自体荧光和生物样本光散射干扰的纳米探针。此外，它们具有优异的光稳定性、尖锐和狭窄的发射以及大的反斯托克斯位移，这使它们具有长期生物成像和实时跟踪的能力。近年来，基于上转换纳米粒子的纳米探针（UC-纳米探针）在生物和医学研究中引起了越来越多的关注。信号对比，即探针和靶标反应前后信号强度的比值，是所有基于反应的探针灵敏度的决定因素。本进展报告介绍了构建 UC-纳米探针的方法，重点介绍了最近提高信号对比的策略，这些策略不断推动了这种探针的生物应用。
