Rare-Earth-Doped Nanoparticles for Short-Wave Infrared Fluorescence Bioimaging and Molecular Targeting of α_Vβ₃-Expressing Tumors

Abstract

The use of short-wave infrared (SWIR) light for fluorescence bioimaging offers the advantage of reduced photon scattering and improved tissue penetration compared to traditional shorter wavelength imaging approaches. While several nanomaterials have been shown capable of generating SWIR emissions, rare-earth-doped nanoparticles (REs) have emerged as an exceptionally bright and biocompatible class of SWIR emitters. Here, we demonstrate SWIR imaging of REs for several applications, including lymphatic mapping, real-time monitoring of probe biodistribution, and molecular targeting of the αvβ3 integrin in a tumor model. We further quantified the resolution and depth penetration limits of SWIR light emitted by REs in a customized imaging unit engineered for SWIR imaging of live small animals. Our results indicate that SWIR light has broad utility for preclinical biomedical imaging and demonstrates the potential for molecular imaging using targeted REs.

Water-Soluble Aza-BODIPYs: Biocompatible Organic Dyes for High Contrast In Vivo NIR-II Imaging

“…Accordingly, there is a need to develop fluorophores that emit in another region of the light spectrum: the NIR-II region (1000–1700 nm, also called shortwave infrared region or SWIR). In this optical region, despite the strong absorption of water at 1400 nm, both scattering and autofluorescence phenomena are reduced, resulting in clearer tissue images compared to those obtained in the NIR-I. ,− The pioneering reports showed that NIR-II fluorophores were nanomaterials (single wall carbon nanotubes, SWCNTs), Ag 2 S and PbS quantum dots, and rare-earth-doped nanoparticles, − highlighting the potential of NIR-II imaging at the preclinical stage. Unfortunately, their clinical application is hampered because of their potential toxicity .…”

Effective design of organic luminogens for near-infrared-II fluorescence imaging and photo-mediated therapy

“…13,14 Therefore, smart advanced materials not only provide an extraordinarily powerful platform to achieve direct monitoring of biological species and activities but also enable the implementation of photo-based therapeutic methods. Recently, several types of organic/inorganic materials have been developed, which include, but are not limited to, rare earth-doped nanomaterials, 15 organic fluorophores, 16 singlewalled carbon nanotubes, 17 and quantum dots. 18 Although inorganic biomaterials have desirable features such as a large Stokes shift, a high quantum yield (QY), little photobleaching, and tuneable optical properties, their usage is often accompanied by safety concerns.…”

The Application of Nanotechnology for the Diagnosis and Treatment of Brain Diseases and Disorders

“…A recent study also reports that sulfated dextran-coated IO NPs can effectively improve bioimaging of the activated microglia-induced brain inflammation by binding to the highly expressed class A scavenger receptors ( Tang et al, 2018 ). In addition, it has also been shown that RE-doped NPs can be used in fluorescence imaging to facilitate the emission of short-wave infrared light after binding to integrin α Vβ3 ( Naczynski et al, 2018 ). In summary, the information above indicates that NPs can be used to improve MI by delivering bioimaging probes or acting as probes themselves, confirming their importance in diagnosis of deep-seated tumor and brain diseases.…”