20种α-氨基酸的太赫兹光谱及其分子结构的相关性(英文)

Correlations between Terahertz Spectra and Molecular Structures of 20 Standard α-Amino Acids

应用太赫兹时域光谱(THz-TDS)技术,在室温下对构成蛋白质的20种基本氨基酸的多晶粉末压片样品进行了光谱测试分析.结果表明,所有氨基酸对THz波反应非常灵敏,在0.2-3.0THz的有效频谱范围内,表现出各自特征吸收峰,故而利用THz光谱可以有效地区别不同种类的氨基酸.我们以新数据验证和补充了前人的研究结果,建立了以氨基酸分子结构及其THz光谱特征为基础的分类方案,讨论并揭示了氨基酸分子的结构差异与其THz吸收光谱之间的相关性.认知这些相关性将有助于鉴定氨基酸分子,促进THz光谱学的理论研究以及在生物医学领域的推广应用.

All 20 standard polycrystalline a-amino acids were examined using terahertz time-domain spectroscopy （THz-TDS） at room temperature. They are strikingly sensitive to the THz pulse and yield a complete set of THz fingerprint spectra between 0.2 and 3.0 THz. These spectra were compared to those from previous reports in terms of spectral shape and frequencies of absorption peaks. We validated the characteristic absorption peaks and provided supplementary data. For the first time, correlations between THz Spectral peaks and the molecular structures of amino acids are revealed and a classification of amino acids based on both molecular structures and THz spectra was established. These correlations can help identify amino acids, trace some functional groups, and examine if the THz spectra are dominated by internal or intermolecular vibrations. These correlations can thus promote the application of THz spectroscopy in the study of biological and medicinal materials in the biomedical fields.