Ding Tao, Li Ruoyu, Zeitler J Axel, Huber Thomas L, Gladden Lynn F, Middelberg Anton P J, Falconer Robert J
Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, Brisbane, Queensland, Australia.
Opt Express. 2010 Dec 20;18(26):27431-44. doi: 10.1364/OE.18.027431.
Terahertz spectra of four alanine-rich peptides with known secondary structures were studied by terahertz time domain spectroscopy (THz-TDS) and by Fourier transform infrared spectroscopy (FTIR) using a synchrotron light source and a liquid-helium cooled bolometer. At ambient temperatures the usable bandwidth was restricted to 0.2-1.5 THz by the absorbance of water. The existence of a solvation shell around the peptide in solution was observed and its size estimated to be between 11 and 17 Å. By cooling the peptide solution to 80 K in order to reduce the water absorbance the bandwidth was increased to 0.1-3.0 THz for both THz-TDS and FTIR. Spectra were consistent with monotonic absorbance of the peptide and the existence of a solid amorphous low density solvation shell.
利用太赫兹时域光谱（THz-TDS）以及使用同步辐射光源和液氦冷却测辐射热计的傅里叶变换红外光谱（FTIR），研究了四种具有已知二级结构且富含丙氨酸的肽的太赫兹光谱。在环境温度下，水的吸收将可用带宽限制在0.2 - 1.5太赫兹。观察到溶液中肽周围存在溶剂化层，其大小估计在11至17埃之间。通过将肽溶液冷却至80 K以降低水的吸收，太赫兹时域光谱和傅里叶变换红外光谱的带宽均增加到0.1 - 3.0太赫兹。光谱与肽的单调吸收以及固态非晶态低密度溶剂化层的存在一致。
