Changes in the supramolecular structures of cellulose after hydrolysis studied by terahertz spectroscopy and other methods
Changes in the supramolecular structures of cellulose after hydrolysis studied by terahertz spectroscopy and other methods
复制标题
太赫兹光谱等方法研究纤维素水解后超分子结构的变化
DOI：
10.1039/c4ra08314h
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发表时间：
2014-01-01
期刊：
影响因子：
3.9
通讯作者：
He, Zhimin
中科院分区：
文献类型：
--
作者：
Guo, Hong;He, Mingxia;He, Zhimin
氢键是结晶纤维素和木质纤维素中的主要作用力之一，然而，如何评价氢键强度的变化仍然是一个很大的挑战。在这里，我们报告了一种新的方法来测量的太赫兹时域光谱（THz-TDS）的纤维素基材料的氢键强度的变化。以微晶纤维素、玉米芯及其酶解后的残余底物为目标纤维素，对该方法进行了验证。在0.5 - 2.5 THz范围内的THz吸收和在0.5 - 1.0 THz范围内的折射率提供了对应于酶水解后残留样品（Avicel和玉米芯）的氢键强度增加的直接信号。并与X射线衍射（XRD）和傅里叶变换红外光谱（FTIR）分析结果进行了比较。作为一种快速、非侵入性的技术，太赫兹光谱提供了关于纤维素基材料氢键强度变化的独特信息。因此，直接评价纤维素大分子的氢键强度是一种很有前途的方法。
Hydrogen bonding is one of dominant forces in crystalline cellulose and lignocellulose, however, it is still a big challenge to evaluate the changes in the hydrogen bonding strength. Here, we reported a new method for measuring the changes in the hydrogen bonding strength of cellulose-based materials by terahertz time domain spectroscopy (THz-TDS). Avicel, corncob and their residual substrates after enzymatic hydrolysis were chosen as the targeted cellulose to demonstrate this method. THz adsorption in the range 0.5–2.5 THz and refractive index in the range 0.5–1.0 THz provided a direct signal corresponding to an increase in the hydrogen bonding strength for the residual samples (Avicel and corncob) after enzymatic hydrolysis. The THz results were further compared with those obtained from X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) analysis. As a quick and non-invasive technique, THz spectroscopy provides unique information about the changes in the hydrogen bonding strength of cellulose-based materials. Therefore, it is a promising way to directly evaluate the hydrogen bonding strength of cellulosic macromolecules.