A synergetic strategy of NIR-Ⅱ squaraine dyes with ultrahigh photothermal conversion efficiency for photothermal therapy  

作　　者：Yigang Wang Guomin Xia Junhui Wang Mingda Wang Weihan Guo Manman Tan Leilei Si Yang Yang Hua Wang Hongming Wang 

机构地区：[1]Institute for Advanced Study and School of Chemistry and Chemical Engineering,Nanchang University,Nanchang,330031,China [2]State Key Laboratory of Molecular Reaction Dynamics and Dynamics Research Center for Energy and Environmental Materials,Dalian Institute of Chemical Physics,Chinese Academy of Sciences,Dalian,116023,China [3]The Second Affiliated Hospital of Nanchang University,Nanchang,330031,China

出　　处：《Science China Chemistry》2024年第2期612-621,共10页中国科学（化学英文版）

基　　金：supported by the National Natural Science Foundation of China (22063005);the Natural Science Foundation of Jiangxi Province (20212ACBA203012,20224BAB214003,20232BAB-203031);the Interdisciplinary Innovation Fund of Natural Science,Nanchang University (9167-27060003-ZD2101,9167-28220007-YB2113)。

摘　　要：Recent research on photothermal therapy(PTT) has sparked significant interest in the development of new organic photothermal agents(PTAs),ranging from single-molecule to aggregated levels.However,controlling aggregation pathways for PTAs with ultrahigh photothermal conversion efficiency(PCE) remains a major challenge.Herein,a two-pronged approach utilizing “Haggregation” and “intramolecular motion” was employed to enhance the PCE of an acceptor-substituted squaraine dye(NSQs).The C2vmolecular symmetry of the NSQs,which possess a ground state dipole moment(μg),promotes H-dimeric aggregates through dipole-dipole counteraction.Peripheral triphenylethylene or diphenylamine groups were added to this H-dimeric nanoplatform.This was done to enhance intramolecular motions for heat generation and also to extend conjugation,which redshifted the optical absorption and balanced the blue-shift induced by H-aggregation.With this technique,an organic PTA with NIR-II absorption was developed,and its nanoparticle achieved a remarkable PCE of 86.3% under 1,064 nm laser excitation.Femtosecond transient absorption spectroscopy and quantum mechanical calculations demonstrated the accelerated internal conversion process in NIR-II PTAs for rapid heat generation.The NSQs nanoparticles exhibit superior photothermal therapeutic properties for in vivo photoacoustic imaging-guided PTT,demonstrating the potential of bottom-up design to enable synergistic engineering strategies towards efficient phototheranostic agents.

关 键 词：squaraine dyes second near-infrared window H-AGGREGATION intramolecular motion photothermal therapy 

分 类 号：TQ617.8[化学工程—精细化工]