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Abstract Multiplex imaging in the second near‐infrared window (NIR‐II, 1000–1700 nm) provides exciting opportunities for more precise understanding of biological processes and more accurate diagnosis of diseases by enabling real‐time acquisition of images with improved contrast and spatial resolution in deeper tissues. Today, the number of imaging agents suitable for this modality remains very scarce. In this work, we have synthesized and fully characterized, including theoretical calculations, a series of dimeric LnIII/GaIIImetallacrowns bearing RuIIpolypyridyl complexes,LnRu‐3(Ln=YIII, YbIII, NdIII, ErIII). Relaxed structures ofYRu‐3in the ground and the excited electronic states have been calculated using dispersion‐corrected density functional theory methods. Detailed photophysical studies ofLnRu‐3have demonstrated that characteristic emission signals of YbIII, NdIIIand ErIIIin the NIR‐II range can be sensitized upon excitation in the visible range through RuII‐centered metal‐to‐ligand charge transfer (MLCT) states. We have also showed that these NIR‐II signals are unambiguously detected in an imaging experiment using capillaries and biological tissue‐mimicking phantoms. This work opens unprecedented perspectives for NIR‐II multiplex imaging using LnIII‐based molecular compounds.
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This content will become publicly available on March 21, 2026
Contrast enhanced photoacoustic tomography of mouse organs using ICG-based J-aggregates
Not AvaIn this study, a novel near-infrared (NIR) ICG-based J-aggregate contrast agent was used for photoacoustic tomography (PAT) to image whole organs in a nude mouse model. NIR-PAT obtained at the 895-nm absorption peak of our nanoparticles, we were able to resolve organs of interest that included the liver and kidney along with vasculature deeper into biological tissue while maintaining fine spatial resolution. NIR-PAT shows promising applications in small-animal functional imaging, including measuring oxygen saturation levels and studying biodistribution of contrast agents, leading to potential clinical imaging studies for drug development and delivery, and angiographic studies.ilable
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- Award ID(s):
- 2128821
- PAR ID:
- 10654803
- Editor(s):
- Intes, Xavier; Ochoa, Marien; Yaseen, Mohammad A
- Publisher / Repository:
- SPIE
- Date Published:
- Page Range / eLocation ID:
- 34
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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