Chen Guo, Yuan Yuhao, Ni Hongli, Ding Guangrui, Li Mingsheng, Zhu Yifan, Li Deming, Zeng Hongru, He Hongjian, Guo Zhongyue, Cheng Ji-Xin, Yang Chen
Department of Electrical and Computer Engineering, Boston University, Boston, MA 02215, USA.
Department of Biomedical Engineering, Boston University, Boston, MA 02215, USA.
Sci Adv. 2025 Jul 4;11(27):eadw4939. doi: 10.1126/sciadv.adw4939. Epub 2025 Jul 2.
Nonradiative photothermal (PT) and photoacoustic (PA) processes have found widespread applications in imaging, stimulation, and therapy. Mapping the generation and propagation of PA and PT waves with high resolution is important to elucidate the interaction between nonradiative fields and biological systems. To this end, we introduce spatial-offset pump-probe imaging (SOPPI). By spatially offsetting the pump beam and the probe beam, SOPPI allows simultaneous imaging of PA/PT wave propagation with nanosecond temporal resolution, micrometer spatial resolution, 65-megahertz detection bandwidth, and a sensitivity of 9.9-pascal noise equivalent pressure. First, the PA and PT evolution from a fiber emitter and the subsequent wave interaction with a mouse skull and brain slices are demonstrated. Then, using water as the absorber, a wavelength-dependent PA/PT generation, evanescent wave-generated PA, and a back-propagated acoustic Mach cone with a tapered fiber are recorded. At last, a SOPPI-PACT is developed to reconstruct the pigment distribution inside a zebrafish larva with high precision and signal-to-noise ratio.
非辐射光热（PT）和光声（PA）过程在成像、刺激和治疗等领域有着广泛的应用。高分辨率地绘制PA和PT波的产生与传播对于阐明非辐射场与生物系统之间的相互作用至关重要。为此，我们引入了空间偏移泵浦-探测成像（SOPPI）。通过在空间上偏移泵浦光束和探测光束，SOPPI能够以纳秒级的时间分辨率、微米级的空间分辨率、65兆赫兹的探测带宽以及9.9帕斯卡的噪声等效压力灵敏度同时对PA/PT波的传播进行成像。首先，展示了光纤发射器产生的PA和PT的演变以及随后波与小鼠头骨和脑切片的相互作用。然后，以水作为吸收体，记录了波长依赖的PA/PT产生、倏逝波产生的PA以及带有锥形光纤的反向传播声学马赫锥。最后，开发了一种SOPPI-PACT，以高精度和信噪比重建斑马鱼幼体内部的色素分布。
