利用太赫兹圆二色性识别手性物质  

Recognition of chiral substances by terahertz circular dichroism

作　　者：纪旭洋 孙爽 张岩[1] Ji Xuyang;Sun Shuang;Zhang Yan(Beijing Key Laboratory of Metamaterials and Devices,Key Laboratory of Terahertz Optoelectronics of Ministry of Education,Department of Physics,Capital Normal University,Beijing 100048,China)

机构地区：[1]首都师范大学物理系,北京市超材料与器件重点实验室,太赫兹光电子学教育部重点实验室,北京100048

出　　处：《光电工程》2024年第5期1-8,共8页Opto-Electronic Engineering

基　　金：北京市教委科技重点资助项目(KZ20231123226)。

摘　　要：不同手性的生物分子具有不同甚至相反的生物和药理活性。由于很多生物大分子的振动和转动能级分布在太赫兹波段,使得太赫兹波谱技术成为生物大分子识别的有效手段,但是太赫兹时域光谱系统都采用线偏振光源,无法对手性分子进行有效识别。我们在理论上利用线偏振的琼斯矩阵模型合成圆偏振下的琼斯矩阵,根据圆偏光的透射率差异性进一步计算样品的透射圆二色光谱,为表征不同手性分子提供了一种有效方法。基于透射式太赫兹时域光谱系统,对(R)-(-)-Ibuprofen和(S)-(+)-Ibuprofen的光谱进行测试,计算了(R)-(-)-Ibuprofen和(S)-(+)-Ibuprofen的线偏透过率和圆偏透过率;并计算出透射性圆二色光谱,两种手性物质的圆二色性值达到0.015,有效地实现了对(R)-(-)-Ibuprofen和(S)-(+)-Ibuprofen的识别效果。这一方法为利用太赫兹光谱技术检测和识别手性分子提供了参考。Biomolecules with different chirality have different or even opposite biological and pharmacological activities.Since vibration and rotation energy levels of many biomolecules lie within the terahertz range,terahertz spectroscopy has emerged as a useful tool for biomolecular identification.Nevertheless,linearly polarized light sources are used in terahertz time-domain spectroscopy,which is ineffective for identifying chiral compounds.We theoretically constructed a circularly polarized Jones matrix using a linearly polarized Jones matrix model.We also calculated the transmission circular dichroism spectrum of the sample based on the difference in transmittance of circularly polarized light,offering a useful technique for describing various chiral compounds.The spectra of(R)-(-)-Ibuprofen and(S)-(+)-Ibuprofen were investigated using a transmission terahertz time-domain spectroscopy system,and the linear polarization biased transmittance and circular polarization transmittance of(R)-(-)-Ibuprofen and(S)-(+)-Ibuprofen were computed.Additionally,the transmittance circular dichroic spectra were calculated,and the two chiral compounds'circular dichroic values reached 0.015,successfully achieving the(R)-(-)-Ibuprofen and(S)-(+)-Ibuprofen recognition effect.This technique serves as a guide for chiral molecule identification and detection using terahertz spectroscopy technology.

关 键 词：琼斯矩阵 圆二色性 太赫兹 手性识别 

分 类 号：O431[机械工程—光学工程]