Phase and Size Control of Core–Shell Upconversion Nanocrystals Light up Deep Dual Luminescence Imaging and CT In Vivo

Abstract

Upconversion nanocrystals (UCNCs) have recently been explored as optical imaging nanoprobes. However, conventional β-NaLuF4 (-) based UCNCs often suffer from large particle size and weak upconversion luminescence (UCL) intensity, leading to poor biocompatibility and low detection sensitivity. Here, a novel strategy for controlling the crystalline phase and size of UCNCs has been developed by doping of yttrium ions, resulting in particle size reduction and phase transition. The total UCL intensity of prepared core-shell UCNCs is significantly enhanced up to ≈4.9 and ≈17.4 times after Tm(3+) and Er(3+) doping than that of core UCNCs, offering deeper tissue UCL imaging with a depth of 8 mm in vivo. Moreover, the CT signal of core-shell UCNCs is ≈1.5 and ≈3.5 times brighter than that of core UCNCs and commercial ioversol agent because of increasing contents of Lu(3+) doped in UCNCs. The synthesized core-shell UCNCs hold a great promise in deep UCL and CT dual-modality imaging in vitro and in vivo.

Polydopamine-Coated Manganese Carbonate Nanoparticles for Amplified Magnetic Resonance Imaging-Guided Photothermal Therapy

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Multifunctional PEGylated Albumin/IR780/Iron Oxide Nanocomplexes for Cancer Photothermal Therapy and MR Imaging

“…It has been previously shown that light within the near infrared (NIR) window (650 - 900 nm) exhibited greatest tissue penetration capability 10 . Consequently, tissue-penetrable NIR-sensitive dyes are often utilized as the photo-responsive agents to generate effects of hyperthermia 11 - 14 , photoacoustics 15 , 16 or photoluminescence 17 within the whole tumor region.…”

Synthesis of a Thermal‐Responsive Dual‐Modal Supramolecular Probe for Magnetic Resonance Imaging and Fluorescence Imaging

“…[ 1,2 ] It relies on advanced medical imaging technique, fusion of multimodality medical imaging, and information on medical cases. [ 3–5 ] Among the common imaging modes, magnetic resonance imaging (MRI) has high spatial resolution but low sensitivity, whereas fluorescence imaging (FI) has high sensitivity but limited depth of penetration. [ 6–8 ] The combination of these two imaging technologies leads to complementary advantages.…”