A Supramolecular Radical Dimer: High‐Efficiency NIR‐II Photothermal Conversion and Therapy

Abstract

Photothermal therapy at the NIR‐II biowindow (1000–1350 nm) is drawing increasing interest because of its large penetration depth and maximum permissible exposure. Now, the supramolecular radical dimer, fabricated by N,N′‐dimethylated dipyridinium thiazolo[5,4‐d]thiazole radical cation (MPT.+) and cucurbit[8]uril (CB[8]), achieves strong absorption at NIR‐II biowindow. The supramolecular radical dimer (2MPT.+‐CB[8]) showed highly efficient photothermal conversion and improved stability, thus contributing to the strong inhibition on HegG2 cancer cell under 1064 nm irradiation even penetrating through chicken breast tissue. This work provides a novel approach to construct NIR‐II chromophore by tailor‐made assembly of organic radicals. It is anticipated that this study provides a new strategy to achieve NIR‐II photothermal therapy and holds promises in luminescence materials, optoelectronic materials, and also biosensing.

Tuning the stability of organic radicals: from covalent approaches to non-covalent approaches

“…[86][87][88][89] The formation of radical dimers may lead to a narrower band gap than the radical itself, and the narrower band gap will further lead to absorption at longer wavelengths. We reported the utilization of an N,N 0 -dimethylated dipyridiniumthiazolo [5,4-d]thiazole radical dimer stabilized in the cavity of cucurbit [8]uril to achieve high-efficiency NIR-II photothermal conversion and therapy 90 (Fig. 19).…”

NIR light-assisted phototherapies for bone-related diseases and bone tissue regeneration: A systematic review

“…Alternatively, the tissue penetration efficacy of NIR light would also influence the efficiency of anticancer phototherapies. The biological window of NIR light can be divided into NIR-I (700-1000 nm), and NIR-II (1000-1300 nm) biowindows 32 , 52 . To date, the NIR-I biowindow has been more commonly used in phototherapies because most kinds of NIR light-responsive nanomaterials have exhibited favorable photothermal and photodynamic properties in the NIR-I biowindow.…”

Boosting Chemodynamic Therapy by the Synergistic Effect of Co-Catalyze and Photothermal Effect Triggered by the Second Near-Infrared Light

“…In addition, the good magnetic properties of FeO endows FeO/MoS 2 -BSA with great potential as contrast agents for MRI [28,29]. This work thus presents a synergistic strategy of NIR II light motivate photothermal effect [30][31][32][33] and co-catalysis to construct nanotheranostic agents with high potency and low side effects.…”