Autofluorescence-Free Targeted Tumor Imaging Based on Luminous Nanoparticles with Composition-Dependent Size and Persistent Luminescence

Abstract

Optical bioimaging is an indispensable tool in modern biology and medicine, but the technique is susceptible to autofluorescence interference. Persistent nanophosphors provide an easy-to-perform and highly efficient means to eliminate tissue autofluorescence. However, direct synthesis of persistent nanophosphors with tunable properties to meet different bioimaging requirements remains largely unexplored. In this work, zinc gallogermanate (ZnGaGeO:Cr, 0 ≤ x ≤ 0.5, ZGGO:Cr) persistent luminescence nanoparticles with composition-dependent size and persistent luminescence are reported. The size of the ZGGO:Cr nanoparticles gradually increases with the increase of x in the chemical formula. Moreover, the intensity and decay time of persistent luminescence in ZGGO:Cr nanoparticles can also be fine-tuned by simply changing x in the formula. In vivo bioimaging tests demonstrate that ZGGO:Cr nanoparticles can efficiently eliminate tissue autofluorescence, and the nanoparticles also show good promise in long-term bioimaging as they can be easily reactivated in vivo. Furthermore, an aptamer-guided ZGGO:Cr bioprobe is constructed, and it displays excellent tumor-specific accumulation. The ZGGO:Cr nanoparticles are ideal for autofluorescence-free targeted bioimaging, indicating their great potential in monitoring cellular networks and construction of guiding systems for surgery.

Recent Progress in Time‐Resolved Biosensing and Bioimaging Based on Lanthanide‐Doped Nanoparticles

“…In the past decade, different kinds of lanthanide‐doped PLNPs have been developed and their biomedical applications have been largely explored, such as in α‐fetoprotein and ascorbic acid detection as well as targeted tumor imaging . Moreover, vis‐to‐NIR or NIR‐to‐NIR lanthanide‐doped PLNPs that can be repeatedly charged in vivo have been developed for achievement of deep tissue and long‐term bioimaging . Due to these unique properties, lanthanide‐doped PLNPs have become ideal probes for highly sensitive biosensing and high resolution bioimaging.…”

“…Recently, our group showed that heterovalence doping is a potent method to tune persistent luminescence intensity and decay time in PLNPs. In our work, Ge 4+ was used as the co‐dopant to tune the persistent luminesce properties of ZnGa 2 O 4 :Cr . Six kinds of PLNPs, Zn 1+ x Ga 2−2 x Ge x O 4 :Cr( x = 0–0.5) were directly synthesized via a hydrothermal method.…”

“…b) Photoluminescence spectrum and c) persistent luminescence decay images of the Zn 1+ x Ga 2–2 x Ge x O 4 :Cr ( x = 0–0.5). a–c) Reproduced with permission . Copyright 2017, American Chemical Society.…”

“…Compared with UV light, visible light can achieve deeper tissue penetration and less phototoxicity. Thus, visible light activatable PLNPs can be reactivated in vivo and are suitable for long‐term bioimaging . Recently, lanthanide‐doped upconversion PLNPs that can be activated with 980 nm laser have been developed.…”

Correlation between ultrabroadband near‐infrared emission and Yb3+/Ni2+ dopants distribution in highly transparent germanate glass‐ceramics containing zinc gallogermanate nanospinels

“…The ZGGO‐based phosphors (eg, Cr 3+ ‐ or Ni 2+ ‐doped ZGGO), possessing good chemical stability and biocompatibility, have attracted increasing attention for their unprecedented super‐long near‐infrared (NIR) persistent photoluminescence (PL) which stems from the unique crystal structures (eg, containing antisite defects) . They have been considered as promising phosphors (both in micropowder and nanoparticle forms) for a wide range of applications including but not limited to night‐vision display, anticounterfeiting, identification marker, and medical diagnostics, etc . It is noted that codoping of RE ions (eg, Pr 3+ , Eu 3+ , Er 3+ , etc.)…”