Photothermal reagents sensitive to near‐infrared (NIR) light are promising imaging agents and therapeutics for anticancer applications because of the deep tissue penetration of NIR light, allowing for spatiotemporal control over the therapeutic activity, with minimal damage to normal tissues. Herein, a new class of NIR‐sensitive biopolymer‐based nanoparticles is presented by covalently conjugating indocyanine green (ICG) onto the surface of naturally occurring glycogen nanoparticles. The resulting ICG‐glycogen conjugates exhibit a markedly enhanced aqueous stability in comparison to free ICG molecules. Furthermore, an efficient light‐to‐heat conversion is enabled by ICG‐glycogen conjugates, as evidenced by the elevated temperatures of their aqueous solutions upon exposure to NIR light. Critically, ICG‐glycogen conjugates are capable of cell internalization, and under NIR irradiation the effective eradication of breast cancer cells, demonstrating their potential in photothermal therapy for cancer.
In the efforts to generate a less toxic X‐Ray bioimaging contrast agent, a fully organic, radioluminescent nanoparticle system that emits in the near‐infrared (NIR) region when excited with an X‐Ray source is synthesized using a two‐step process. First, red‐emitting nanoparticles are fabricated by the emulsion copolymerization of styrene and propargyl acrylate with anthracene, naphthalimide, and rhodamine B methyl methacrylate derivatives. Subsequently, the nanoparticles are modified with silicon phthalocyanine and indocyanine green derivatives via a copper(I)‐catalyzed azide/alkyne cycloaddition “click” reaction. By coupling an organic scintillator with four Förster resonance energy transfer‐pairing dyes, X‐Ray‐induced, multiple, sequential energy transfer is exploited to convert ionizing radiation from an X‐Ray source into NIR light, which is optimal for biomedical imaging. Proof‐of‐concept imaging studies show that the X‐Ray‐induced indocyanine green fluorescence from the particulate system can be visualized through porcine tissue. Additionally, toxicity studies in human embryonic kidney cells indicate that the particles are nontoxic and applicable
- NSF-PAR ID:
- 10514545
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Photonics Research
- Volume:
- 5
- Issue:
- 6
- ISSN:
- 2699-9293
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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