AbstractAchieving photothermal therapy (PTT) at ultralow laser power density is crucial for minimizing photo‐damage and allowing for higher maximum permissible skin exposure. However, this requires photothermal agents to possess not just superior photothermal conversion efficiency (PCE), but also exceptional near‐infrared (NIR) absorptivity. J‐aggregates, exhibit a significant redshift and narrower absorption peak with a higher extinction coefficient. Nevertheless, achieving predictable J‐aggregates through molecular design remains a challenge. In this study, we successfully induced desirable J‐aggregation (λabsmax: 968 nm, ϵ: 2.96×105 M−1 cm−1, λemmax: 972 nm, ΦFL: 6.2 %) by tuning electrostatic interactions between π‐conjugated molecular planes through manipulating molecular surface electrostatic potential of aromatic ring‐fused aza‐BODIPY dyes. Notably, by controlling the preparation method for encapsulating dyes into F‐127 polymer, we were able to selectively generate H‐/J‐aggregates, respectively. Furthermore, the J‐aggregates exhibited two controllable morphologies: nanospheres and nanowires. Importantly, the shortwave‐infrared J‐aggregated nanoparticles with impressive PCE of 72.9 % effectively destroyed cancer cells and mice‐tumors at an ultralow power density of 0.27 W cm−2 (915 nm). This phototherapeutic nano‐platform, which generates predictable J‐aggregation behavior, and can controllably form J‐/H‐aggregates and selectable J‐aggregate morphology, is a valuable paradigm for developing photothermal agents for tumor‐treatment at ultralow laser power density.
摘要在超低激光功率密度下实现光热疗法(P
TT)对于最大限度地减少光损伤和提高皮肤最大允许暴露量至关重要。然而,这就要求光热制剂不仅要具有卓越的光热转换效率(PCE),还要具有超强的近红外(NIR)吸收能力。J 聚合物具有明显的红移,吸收峰更窄,消光系数更高。然而,通过分子设计实现可预测的 J-聚集体仍然是一项挑战。在本研究中,我们通过操纵芳香环融合 aza-BODIPY
染料的分子表面静电势,调整 π 共轭分子平面之间的静电相互作用,成功诱导出理想的 J 聚合(λabsmax:968 nm,ϵ:2.96×105 M-1 cm-1,λemmax:972 nm,ΦFL:6.2 %)。值得注意的是,通过控制将
染料封装到 F-127 聚合物中的制备方法,我们能够分别选择性地生成 H-/J- 聚合物。此外,J 聚合物呈现出两种可控形态:纳米球和纳米线。重要的是,短波-红外线 J-聚合纳米粒子的 PCE 值高达 72.9%,在 0.27 W cm-2 的超低功率密度(915 nm)下可有效摧毁癌细胞和小鼠肿瘤。这种光治疗纳米平台可产生可预测的 J-聚集行为,并能可控地形成 J-/H- 聚集体和可选择的 J-聚集体形态,是在超低激光功率密度下开发用于肿瘤治疗的光热制剂的一个宝贵范例。