Organic NIR-II Photoacoustic Agent Utilizing Combined Two-Photon and Excited State Absorption at 1064 nm
Organic NIR-II Photoacoustic Agent Utilizing Combined Two-Photon and Excited State Absorption at 1064 nm
复制标题
利用 1064 nm 处双光子和激发态吸收相结合的有机 NIR-II 光声剂
DOI：
10.1021/acsphotonics.0c01227
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发表时间：
2020-11-18
期刊：
影响因子：
7
通讯作者：
Prasad, Paras N.
中科院分区：
文献类型：
--
作者：
Hu, Wenbo;Zhang, Huijuan;Prasad, Paras N.
在生物透明的第二光学窗口(NIR-II，1000-1700 nm)内的波长进行光声成像，光散射大大减少，对于临床前和临床实践具有重要意义。然而，PA造影剂在NIR-II区强吸收的稀有性极大地限制了其实际应用。这项研究揭示了一类新的近红外吸收有机BODIPY分子(2B-BDP)的NIR-II PA试剂，用于通过双光子吸收(TPA)和激发态吸收(ESA)进行NIR-II PA成像。飞秒瞬时吸收光谱和非线性透过率实验明确地揭示了2B-BDP的TPA诱导的ESA光物理过程。通过TPA和ESA的联合贡献，2B-BDP在1064 nm附近有足够的吸收，然后进行高效的非辐射衰减，显示出强烈的NIR-II PA信号。这项研究可以用一种简单、可扩展、省时、经济的方法来开发NIR-II有机PA试剂。
Photoacoustic (PA) imaging performed at a wavelength within the second optical window of biological transparency (NIR-II, 1000-1700 nm), where light scattering is greatly reduced, is of great significance for preclinical and clinical practices. However, the rarity of PA contrast agents strongly absorbing in the NIR-II region has greatly limited its practical applications. The study presented here reveals a new class of NIR-II PA agents using a near-infrared absorbing organic BODIPY molecule (2B-BDP) for NIR-II PA imaging via two-photon absorption (TPA) followed by excited state absorption (ESA). Femtosecond transient absorption (fs-TA) spectroscopy and nonlinear transmittance experiments unambiguously reveal an efficient TPA-induced ESA photophysical process for 2B-BDP. By virtue of sufficient absorption around 1064 nm through the combined contributions of TPA and ESA followed by a highly efficient nonradiative decay, 2B-BDP exhibits a strong NIR-II PA signal. This study can lead to the development of NIR-II organic PA agents with an easy, scalable, time-, and cost-effective approach.