Lanthanide-Doped Upconversion Nanoparticles for Super-Resolution Microscopy

Abstract

Super-resolution microscopy offers a non-invasive and real-time tool for probing the subcellular structures and activities on nanometer precision. Exploring adequate luminescent probes is a great concern for acquiring higher-resolution image. Benefiting from the atomic-like transitions among real energy levels, lanthanide-doped upconversion nanoparticles are featured by unique optical properties including excellent photostability, large anti-Stokes shifts, multicolor narrowband emissions, tunable emission lifetimes, etc. The past few years have witnessed the development of upconversion nanoparticles as probes for super-resolution imaging studies. To date, the optimal resolution reached 28 nm (λ/36) for single nanoparticles and 82 nm (λ/12) for cytoskeleton structures with upconversion nanoparticles. Compared with conventional probes such as organic dyes and quantum dots, upconversion nanoparticle-related super-resolution microscopy is still in the preliminary stage, and both opportunities and challenges exist. In this perspective article, we summarized the recent advances of upconversion nanoparticles for super-resolution microscopy and projected the future directions of this emerging field. This perspective article should be enlightening for designing efficient upconversion nanoprobes for super-resolution imaging and promote the development of upconversion nanoprobes for cell biology applications.

NIR-II Upconversion Photoluminescence of Er3+ Doped LiYF4 and NaY(Gd)F4 Core-Shell Nanoparticles

“…As an unusual anti-stokes process, photon upconversion (UC) refers to converting several low-energy photons to one high-energy photon ( Zhou et al, 2015 ; Wei et al, 2016 ). Due to the non-linear instincts, UC materials are well-developed for bio-imaging ( Gonzalez-Bejar et al, 2016 ; Chen et al, 2021 ), photo-dynamics therapy( Lucky et al, 2015 ; Liu et al, 2019 ; Jia et al, 2020 ), and single particle imaging ( Gargas et al, 2014 ; Liu et al, 2017 ; Zhou et al, 2020b ; Dong et al, 2021 ).…”

Super-Resolution Microscopy: Shedding New Light on In Vivo Imaging

“…Current NIR fluorophores are mostly developed based on small organic dyes, inorganic materials, or organic-inorganic hybrid materials. For example, the lanthanide-doped upconversion nanoparticles (UCNPs) have been introduced in super-resolution imaging because of the properties of low excitation power, narrow-band emission, zero auto-fluorescence, large anti-Stokes shifts and high-photostability ( Dong et al, 2020 ; Hu et al, 2020 ). In 2018, Jin’s group developed near-infrared emission saturation (NIRES) nanoscopy applying UCNPs to realize super-resolution imaging in deep tissue.…”

Review on Nanoparticles and Nanostructured Materials: Bioimaging, Biosensing, Drug Delivery, Tissue Engineering, Antimicrobial, and Agro-Food Applications

“…The nanoparticles optical and physical features can be tailored by structure amplification, which is their most distinctive advantage for optical imaging. Ceramic nanomaterials (mesoporous TiO 2 and SiO 2 NPs) also are among the most interesting candidates for bioimaging because of their size-manageable morphology, easy functionalization, and biocompatible hydrophilic surface [ 46 , 47 ]. FDA-approved silica is less toxic and is biocompatible [ 48 ].…”