Lee Sang-Hun, Shin Seulgi, Roh Yeeun, Oh Seung Jae, Lee Soo Hyun, Song Hyun Seok, Ryu Yong-Sang, Kim Yun Kyung, Seo Minah
Sensor System Research Center, Korea Institute of Science and Technology, Seoul, 02792, Republic of Korea.
Convergence Research Center for Diagnosis, Treatment and Care System of Dementia, Korea Institute of Science and Technology, Seoul, 02792, Republic of Korea; Division of Bio-Medical Science & Technology, KIST School, Korea University of Science and Technology (UST), Seoul, 02792, Republic of Korea.
Biosens Bioelectron. 2020 Dec 15;170:112663. doi: 10.1016/j.bios.2020.112663. Epub 2020 Sep 28.
Terahertz (THz) imaging technology has shown significant potential for use in biomedical imaging owing to its non-ionizing characteristics by its low photon energy and its ultrabroadband spectral comparability with many molecular vibrational resonances. However, despite the significant advantage of being able to identify bio-materials in label-free configurations, most meaningful signals are buried by huge water absorption, thus it is very difficult to distinguish them using the small differences in optical constants at THz regime, limiting the practical application of this technology. Here, we demonstrate advanced THz imaging with enhanced color contrast by the use of THz field that is localized and enhanced by a nanometer-scale slot array. THz images of a biological specimen, such as mouse brain tissue and fingerprint, on a nano-slot array-based metamaterial sensing chip, which is elaborately fabricated in large-area, show a higher contrast and clearer boundary information in reflectance without any labeling. A reliable numerical solution to find accurate optical constants using THz nano-slot resonance for the quantitative analysis of target bio-specimens is also introduced. Finally, the precise optical properties of real bio-samples and atlas information are provided for specific areas where amyloid beta proteins, known to cause dementia, have accumulated in a mouse brain.
太赫兹（THz）成像技术因其低光子能量的非电离特性以及与许多分子振动共振的超宽带光谱可比性，在生物医学成像中显示出巨大潜力。然而，尽管能够在无标记配置中识别生物材料具有显著优势，但大多数有意义的信号都被巨大的水吸收所掩盖，因此在太赫兹波段利用光学常数的微小差异来区分它们非常困难，这限制了该技术的实际应用。在此，我们展示了一种先进的太赫兹成像技术，通过使用由纳米级狭缝阵列局部化和增强的太赫兹场，增强了颜色对比度。在大面积精心制作的基于纳米狭缝阵列的超材料传感芯片上，对生物样本（如小鼠脑组织和指纹）进行的太赫兹成像，在反射率方面显示出更高的对比度和更清晰的边界信息，且无需任何标记。还介绍了一种可靠的数值解决方案，利用太赫兹纳米狭缝共振来寻找准确的光学常数，用于对目标生物样本进行定量分析。最后，针对已知会导致痴呆的β淀粉样蛋白在小鼠大脑中积累的特定区域，提供了真实生物样本的精确光学特性和图谱信息。
