School of Chemistry, Monash University, Clayton, VIC 3800, Australia.
Australian Regenerative Medicine Institute, Monash University, Clayton, VIC 3800, Australia; Monash Biomedical Imaging, Monash University, Clayton, VIC 3800, Australia.
Ultrason Sonochem. 2022 May;86:106041. doi: 10.1016/j.ultsonch.2022.106041. Epub 2022 May 18.
The current work features process parameters for the ultrasound (25 kHz)-assisted fabrication of polydopamine-shelled perfluorocarbon (PDA/PFC) emulsion droplets with bimodal (modes at 100-600 nm and 1-6 µm) and unimodal (200-600 nm) size distributions. Initial screening of these materials revealed that only PDA/PFC emulsion droplets with bimodal distributions showed photoacoustic signal enhancement due to large size of their optically absorbing PDA shells. Performance of this particular type of emulsion droplets as photoacoustic agents were evaluated in Intralipid®-India ink media, mimicking the optical scattering and absorbanceof various tissuetypes. From these measurements, it was observed that PDA/PFC droplets with bimodal size distributions can enhance the photoacoustic signal of blood-mimicking phantom by up to five folds in various tissue-mimicking phantoms with absorption coefficients from 0.1 to 1.0 cm. Furthermore, using the information from enhanced photoacoustic images at 750 nm, the ultimate imaging depth was explored for polydopamine-shelled, perfluorohexane (PDA/PFH) emulsion droplets by photon trajectory simulations in 3D using a Monte Carlo approach. Based on these simulations, maximal tissue imaging depths for PDA/PFH emulsion droplets range from 10 to 40 mm, depending on the tissue type. These results demonstrate for the first time that ultrasonically fabricated PDA/PFC emulsion droplets have great potential as photoacoustic imaging agents that can be complemented with other reported characteristics of PDA/PFC emulsion droplets for extended applications in theranostics and other imaging modalities.
当前的工作以超声（25 kHz）辅助制备具有双峰（模式在 100-600nm 和 1-6μm）和单峰（200-600nm）尺寸分布的聚多巴胺壳层全氟碳（PDA/PFC）乳液液滴的工艺参数为特色。对这些材料的初步筛选表明，只有具有双峰分布的 PDA/PFC 乳液液滴由于其光学吸收 PDA 壳的大尺寸而显示出光声信号增强。在 Intralipid®-印度墨水介质中评估了这种特殊类型的乳液液滴作为光声剂的性能，模拟了各种组织类型的光散射和吸收率。从这些测量中可以观察到，具有双峰尺寸分布的 PDA/PFC 液滴可以在吸收系数为 0.1 至 1.0 cm 的各种组织模拟体模中，将血模拟体模的光声信号增强高达五倍。此外，使用在 750nm 处增强的光声图像的信息，通过在 3D 中使用蒙特卡罗方法进行光子轨迹模拟，研究了聚多巴胺壳层的全氟己烷（PDA/PFH）乳液液滴的最终成像深度。基于这些模拟，PDA/PFH 乳液液滴的最大组织成像深度范围为 10 至 40mm，具体取决于组织类型。这些结果首次表明，超声制造的 PDA/PFC 乳液液滴具有作为光声成像剂的巨大潜力，可与 PDA/PFC 乳液液滴的其他报道特性相结合，以在治疗学和其他成像模式中扩展应用。
