超分辨光学显微成像的新武器——镧系离子掺杂上转换纳米荧光探针(特邀)

A New Weapon For Super-Resolution Imaging:Lanthanide Ion Doped Upconversion Nanoparticles(Invited)

超分辨荧光成像技术因其能够突破光学衍射极限的限制,为生命科学研究带来全新的观察尺度而获得了诺贝尔化学奖。但是,传统的超分辨荧光显微镜需要极为复杂的光学系统来突破衍射极限,通常伴随着明显的光毒性和低时间分辨率,昂贵的造价以及日益复杂的操作限制了其在生物医学领域中的推广应用。因此,全球各大研究团队都在积极寻求具有近红外、高亮度和抗光漂白的替代荧光探针,并通过改善成像装置与算法,进一步拓展超分辨显微技术的应用范围。稀土元素纳米材料由于其独特而优异的物理化学特性,如显著的反斯托克斯光谱位移、无背景噪声、抗光漂白、光稳定性、低毒性和高成像穿透能力等,持续受到化学、物理学和材料学领域的广泛关注,是近期兴起的一种稳定性优异的无机荧光探针。本文首先简要介绍了上转换纳米颗粒的发光机制,然后讨论了纳米结构材料中实现光子上转换的主要限制。此外还介绍了镧系元素掺杂上转换纳米粒子在超分辨生物成像、分子检测等领域的应用,以及介绍了包括降低激光功率要求和耦合技术难度、提高激光直扫成像分辨率与速度、提高多路复用成像效率等应用技术优势。最后重点介绍了颗粒合成方面的主要挑战、可行的改进措施以及对未来发展的展望,为稀土纳米材料在生命科学成像领域的推广应用提供有力的理论基础与技术支撑。

Optical super-resolution imaging technology,acknowledged by the Nobel Prize in Chemistry for transcending optical diffraction limits,has revolutionised life science research with its groundbreaking observation scale.However,conventional super-resolution fluorescence microscopes face challenges,requiring intricate optical systems that often result in significant phototoxicity and low temporal resolution,limiting their widespread use in biomedical research.Therefore,research teams actively seek alternative fluorescent probes with near-infrared capabilities,high brightness,and resistance to photobleaching,aiming to extend the application of super-resolution microscopy in biomedical research.Rare-earth nanomaterials,renowned for their exceptional physicochemical properties such as anti-Stokes spectral shift,lack of background noise,resistance to photobleaching,photostability,low toxicity,and high imaging penetration,have emerged as stable and superior inorganic fluorescent probes.This review paper provides a brief overview of the luminescent mechanism of upconversion nanoparticles,exploring the primary constraints in achieving photon upconversion in nanostructured materials.Additionally,it highlights the applications and advantages of lanthanide-doped upconversion nanoparticles in super-resolution biological imaging,molecular detection,and other domains.These advantages encompass reducing laser power requirements,addressing technical challenges in coupling,improving laser scanning imaging resolution and speed,and enhancing multiplexing imaging efficiency.This paper concludes by emphasizing significant challenges in particle synthesis,proposing feasible improvement measures,and outlining prospects for future development.It establishes a robust theoretical foundation and provides technical support for the widespread integration of rare-earth nanomaterials in the field of life imaging sciences.