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Coupling molecular rigidity and flexibility on fused backbones for NIR-II photothermal conversion
Yonglin He1, Hailiang Liao2, Shanzhi Lyu1
1Department of Chemistry, Renmin University of China Beijing 100872 China yapeiwang@ruc.edu.cn.
Chemical Science
|June 24, 2021
Summary
Researchers developed new organic polymers for near-infrared II (NIR-II) photothermal conversion. This strategy enhances light absorption and heat generation for deeper tissue applications.
Area of Science:
- Materials Science
- Polymer Chemistry
- Biomedical Engineering
Background:
- Growing interest in photothermal conversion within the near-infrared II (NIR-II) window (1000-1350 nm) due to enhanced tissue penetration.
- Limited development of organic photothermal polymers and theoretical frameworks for efficient NIR-II applications.
- Need for molecular design strategies to optimize photothermal conversion efficiency in the NIR-II region.
Purpose of the Study:
- To propose and synthesize novel organic polymers with enhanced photothermal conversion capabilities in the NIR-II window.
- To investigate the relationship between polymer structure, specifically coupled rigidity and flexibility, and photothermal performance.
- To provide a conceptual framework for designing future NIR-II photothermal polymers.
Main Methods:
- Design of a fused backbone polymer structure incorporating intramolecular hydrogen bonding and double bonds.
- Synthesis of a specific class of NIR-II photothermal polymers based on the proposed design.
- Evaluation of photothermal conversion efficiency and correlation with molecular properties (rigidity/flexibility) in ground and excited states.
Main Results:
- Successful preparation of NIR-II photothermal polymers exhibiting remarkable conversion efficiencies.
- Demonstration that the coupled rigidity and flexibility strategy enhances light absorption from the ground to the excited state.
- Confirmation that nonradiative emission from the excited to the ground state contributes to efficient heat generation.
Conclusions:
- The proposed fused backbone structure effectively couples polymer rigidity and flexibility, leading to superior NIR-II photothermal performance.
- This strategy significantly improves light absorption and nonradiative decay pathways crucial for efficient photothermal conversion.
- The concept of coupling polymeric rigidity and flexibility offers a promising avenue for developing advanced NIR-II photothermal materials.
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