低温下手性糖类的太赫兹吸收光谱和手性光谱

Terahertz absorption spectra and chiral spectra of saccharides at low temperature

摘要:

糖类是典型的手性物质，其在太赫兹波段的手性光谱尚未得到充分研究。本文研究了乳糖、半乳糖、葡萄糖3种糖类在低温和常温下的折射率和吸收谱，并通过太赫兹时域偏振光谱检测，获得了这些样品的手性光谱。实验结果显示，糖类吸收会随着温度降低而减弱，低温下有利于获得样品的手性特征；在80 K温度下，葡萄糖在1.3~1.5 THz频段表现出很强的圆二色性(CD)，在1.39 THz处CD谱峰值达到44.97%；在1.6~1.8 THz频段内，3种糖类都具有特定的手性特征峰，CD值均超过20%。研究结果对进一步认识手性生化样品在太赫兹波段的手性光谱及其内在机制具有重要参考价值。

Abstract:

Saccharides are typical chiral substances, and their chiral spectra in the terahertz band have not been fully studied. The refractive index and absorption spectra of lactose, galactose, and glucose at low temperature and normal temperature are studied respectively, and the chiral spectra of these samples are obtained through terahertz time-domain polarization spectroscopy. The experimental results show that the absorption of saccharides will decrease as the temperature decreases, which is conducive to obtain the chiral characteristics of the sample at low temperature. At 80 K, glucose exhibits strong Circular Dichroism(CD) in 1.3-1.5 THz; the CD peak value reaches 44.97% at 1.39 THz. All three saccharides have specific chiral characteristic peaks, and the CD values all exceed 20% in 1.6-1.8 THz. The research results can provide important reference for further understanding of the chiral spectra of chiral biochemical samples in terahertz band and their internal mechanisms.