Department of Chemistry and Biochemistry, Graduate School of Engineering, Center for Molecular Systems (CMS), Kyushu University, 744 Moto-oka, Nishi-ku, Fukuoka, 819-0395, Japan.
JST-PRESTO, Honcho 4-1-8, Kawaguchi, Saitama, 332-0012, Japan.
Angew Chem Int Ed Engl. 2020 Jun 22;59(26):10252-10264. doi: 10.1002/anie.202001325. Epub 2020 Apr 2.
The addition of stimuli-responsiveness to anti-Stokes emission provides a unique platform for biosensing and chemosensing. Particularly, stimuli-responsive photon upconversion based on triplet-triplet annihilation (TTA-UC) is promising due to its occurrence at low excitation intensity with high efficiency. This Minireview summarizes the recent developments of TTA-UC switching by external stimuli such as temperature, oxygen, chemicals, light, electric field, and mechanical force. For the systematic understanding of the underlying general mechanisms, the switching mechanisms are categorized into four types: 1) aggregation-induced UC; 2) assembly-induced air-stable UC; 3) diffusion-controlled UC; and 4) energy-transfer-controlled UC. The development of stimuli-responsive smart TTA-UC systems would enable sensing with unprecedented sensitivity and selectivity, and expand the scope of TTA-UC photochemistry by combination with supramolecular chemistry, materials chemistry, mechanochemistry, and biochemistry.
反斯托克斯发射的刺激响应为生物传感和化学传感提供了独特的平台。特别是，基于三重态-三重态湮灭（TTA-UC）的刺激响应上转换由于其在低激发强度下具有高效率而具有很大的应用前景。本文综述了通过温度、氧、化学物质、光、电场和机械力等外部刺激来实现 TTA-UC 转换的最新进展。为了系统地理解其基本的一般机制，将转换机制分为以下四种类型：1）聚集诱导的 UC；2）组装诱导的空气稳定 UC；3）扩散控制的 UC；和 4）能量转移控制的 UC。刺激响应智能 TTA-UC 系统的发展将使传感具有前所未有的灵敏度和选择性，并通过与超分子化学、材料化学、机械化学和生物化学相结合，扩展 TTA-UC 光化学的范围。
