Shi Chenjun, Yan Yan, Mehrmohammadi Mohammad, Zhang Jitao
Department of Biomedical Engineering, College of Engineering, Wayne State University, Detroit, MI 48202, USA.
Department of Imaging Science, School of Medicine and Dentistry, University of Rochester Medical Center, Rochester, NY, 14642, USA.
bioRxiv. 2023 Mar 12:2023.03.10.532144. doi: 10.1101/2023.03.10.532144.
Multimodal optical imaging techniques are useful for various applications, including imaging biological samples for providing comprehensive material properties. In this work, we developed a new modality that can measure a set of mechanical, optical, and acoustical properties of a sample at microscopic resolution, which is based on the integration of Brillouin (Br) and photoacoustic (PA) microscopy. The proposed multimodal imaging technique not only can acquire co-registered Br and PA signals but also allows us to utilize the sound speed measured by PA to quantify the sample’s refractive index, which is a fundamental property of the material and cannot be measured by either technique individually. We demonstrated the colocalization of Br and time-resolved PA signals in a synthetic phantom made of kerosene and CuSO aqueous solution. In addition, we measured the refractive index of saline solutions and validated the result against published data with a relative error of 0.3 %. This multimodal Br-PA modality could open a new way for characterizing biological samples in physiological and pathological conditions.
多模态光学成像技术适用于各种应用，包括对生物样本进行成像以提供全面的材料特性。在这项工作中，我们开发了一种新的模态，它能够在微观分辨率下测量样本的一组机械、光学和声学特性，该模态基于布里渊（Br）显微镜和光声（PA）显微镜的集成。所提出的多模态成像技术不仅可以获取配准的Br和PA信号，还使我们能够利用PA测量的声速来量化样本的折射率，折射率是材料的一个基本特性，而这两种技术单独都无法测量。我们在由煤油和硫酸铜水溶液制成的合成体模中展示了Br和时间分辨PA信号的共定位。此外，我们测量了盐溶液的折射率，并将结果与已发表的数据进行了验证，相对误差为0.3%。这种多模态Br-PA模态可能为在生理和病理条件下表征生物样本开辟一条新途径。
