聚酰胺/硅胶吸附剂吸附分离茶多酚的红外光谱

用傅里叶变换红外光谱研究了室温下聚酰胺／硅胶吸附剂（ Ｐ Ａ／ Ｓｉ Ｏ２）对茶叶中茶多酚的分离提取原理．红外光谱表明， Ｐ Ａ／ Ｓｉ Ｏ２ 中 Ｐ Ａ 分子的酰胺基－ Ｏ‖ Ｃ－ Ｎ Ｈ－ 是通过氢键吸附茶多酚分子的活性基团，而酰胺基对咖啡因分子没有吸附作用． Ｐ Ａ／ Ｓｉ Ｏ２ 中 Ｓｉ Ｏ２ 表面羟基 Ｏ Ｈ 是吸附咖啡因及茶多酚分子的活性基团．由于氢键的作用，茶多酚和咖啡因分子之间也能相互吸附． Ｐ Ａ／ Ｓｉ Ｏ２ 对氨基酸类物质不起吸附作用，因而容易将其分离．

IR Absorption Spectra of Tea Polyphenol Extracted by PA/SiO2

The principle of tea polyphenol extracted by polyamide on silica adsorbent (PA/SiO 2) at room temperature was studied with FTIR Spectroscopy. The obtained IR spectra showed that the amide group C O NH- of the PA molecule of PA/SiO 2 adsorbed the active group of tea polyphenol molecule through hydrogen bonding and did not adsorb the caffeine molecule. The surface hydroxyl group on the SiO 2 of PA/SiO 2 was the reactive group which adsorbed caffeine and tea polyphend molecules, and the tea polyphenol and caffeine molecules can also adsorb each othe via hydrogen bonding. Substances like amino acids were not adsorbed by PA/SiO 2 and thus easily separated.