State Key Laboratory of Organic Electronics and Information Displays & Jiangsu Key Laboratory for Biosensors, Institute of Advanced Materials (IAM), Nanjing University of Posts & Telecommunications, Nanjing 210023, China.
J Mater Chem B. 2024 Aug 28;12(34):8383-8388. doi: 10.1039/d4tb01198h.
Conjugated polymers (CPs), which emit in the second near-infrared window (NIR-II, 1000-1700 nm), are used as biomaterials for NIR-II fluorescence imaging because of their adjustable photophysical properties and high optical stability. However, the fluorescence signal of conventional CPs is quenched in an aggregated state due to strong π-π stacking, which results in the closure of the radiation attenuation pathway. To solve this problem, the aggregation-induced emission effect is considered a reasonable strategy for enhancing the aggregative fluorescence of IR-II emitters. We herein report NIR-II conjugated polymers with typical AIE characteristics ( > 3) by changing the side chain structure of receptor units and the conjugation degree of donors. Conjugated polymer nanoparticles (PBVT NPs) exhibit outstanding performance in NIR-II fluorescence imaging (QY = 1.94%) and highly effective photothermal therapy ( = 45%). studies have shown that the location of tumors can be accurately obtained by NIR-II FL/NIR-II PA imaging, and there is a significant anti-tumor effect after laser irradiation. This work offers prospects for the design of multifunctional conjugated polymers for NIR-II FL/PA imaging to guide NIR-II PTT applications.
共轭聚合物（CPs）在近红外二区（NIR-II，1000-1700nm）中发射，因其可调的光物理性质和高光学稳定性而被用作 NIR-II 荧光成像的生物材料。然而，由于强π-π堆积，常规 CPs 的荧光信号在聚集状态下被猝灭，这导致辐射衰减途径的关闭。为了解决这个问题，聚集诱导发射效应被认为是增强 IR-II 发射器聚集荧光的合理策略。我们通过改变受体单元的侧链结构和供体的共轭度，报告了具有典型 AIE 特性（>3）的 NIR-II 共轭聚合物。共轭聚合物纳米粒子（PBVT NPs）在 NIR-II 荧光成像（QY=1.94%）和高效光热治疗（=45%）方面表现出优异的性能。研究表明，通过 NIR-II FL/NIR-II PA 成像可以准确获得肿瘤位置，并且激光照射后具有显著的抗肿瘤效果。这项工作为设计用于 NIR-II FL/PA 成像的多功能共轭聚合物以指导 NIR-II PTT 应用提供了前景。
