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A Bright NIR-II Fluorescence Probe for Vascular and Tumor Imaging
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Fluorescent J‑Aggregates in the NIR-II Window: Unlocking Frontiers in Biomedical Imaging
1MOE Key Laboratory for Biomedical Photonics, Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430074, China.
Chemical & Biomedical Imaging
|June 26, 2026
Summary
J-aggregation offers a facile route to high-performance second near-infrared window (NIR-II) fluorophores for biomedical imaging. This strategy overcomes limitations of traditional methods, enabling deeper visualization of living systems.
Area of Science:
- Biomedical Imaging
- Organic Chemistry
- Materials Science
Background:
- Fluorescent organic dyes are crucial for biomedical imaging.
- Developing probes for the second near-infrared window (NIR-II) is essential for deeper biological visualization.
- Current NIR-II fluorophore development faces challenges like synthetic complexity and aggregation-caused quenching (ACQ).
Purpose of the Study:
- To explore J-aggregation as an alternative strategy for high-performance NIR-II fluorophores.
- To analyze design principles for J-aggregate formation in various molecular scaffolds.
- To synthesize recent applications of J-aggregates in bioimaging, biosensing, and theranostics.
Main Methods:
- Review and analysis of design principles for J-aggregate formation.
- Examination of diverse molecular scaffolds including cyanines and BODIPY derivatives.
- Synthesis of recent applications in bioimaging, biosensing, and theranostics.
Main Results:
- J-aggregation provides a facile and spectrally tunable approach to NIR-II emission.
- This strategy circumvents synthetic complexity and aggregation-caused quenching (ACQ).
- Diverse molecular scaffolds can be engineered to form J-aggregates for enhanced optical properties.
Conclusions:
- J-aggregation is a promising strategy for developing advanced NIR-II fluorophores.
- Further research is needed to address challenges like low quantum yield and in vivo stability for clinical translation.
- Optimizing J-aggregates will advance their routine use in biomedicine.
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