低浓度下的仿生矿化及其在对映体拆分中的应用  

Biomimetic Mineralization at a Dilute Concentration and Application in Enantioseparation

作　　者：贺洋洋 李艺[1] 李宝宗[1] 杨永刚[1] HE Yangyang;LI Yi;LI Baozong;YANG Yonggang(College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, China)

机构地区：[1]苏州大学材料与化学化工学部,苏州215123

出　　处：《高等学校化学学报》2019年第2期393-402,共10页Chemical Journal of Chinese Universities

基　　金：国家自然科学基金(批准号:21574095;51473106)资助~~

摘　　要：以L-苯丙氨酸衍生物(L-18Phe6PyBr)的自组装体为模板,在0. 30 mmol/L的浓度下,研究了p H值、老化时间和四乙氧基硅烷(TEOS)浓度对二氧化硅形貌的影响.通过扫描电子显微镜和透射电子显微镜对样品进行表征.结果表明,在p H=10. 01的条件下可以得到左手扭转的纳米带,而p H=7. 15和12. 34时,得到直线的纳米带.遵循动态模板的方法,老化时间的延长有利于直线纳米带的形成.随着TEOS和L-18Phe6PyBr的质量比由2∶1增加到15∶1,扭转纳米带的宽度增加,螺距变长.通过煅烧除去有机模板后,得到带状二氧化硅纳米管.将TEOS与L-18Phe6PyBr质量比为2∶1制备得到的二氧化硅作为气相色谱固定相,涂渍到毛细管色谱柱中进行对映体拆分.结果表明,该气相色谱柱可以拆分1-苯基-1-丙醇、1-(4-氯苯基)乙醇和2-甲基戊酸3种外消旋化合物,手性超分子印迹是拆分对映体的主要作用力.对二氧化硅低聚物与小分子凝胶的协同组装行为以及将无机材料作为手性固定相有了一个更好的认识.The morphologies and pore architectures of silicas were controlled by tuning the pH value, aging time and the concentration of tetraethoxysilane(TEOS) using the self-assemblies of an L -phenylalanine derivative ( L -18Phe6PyBr) at a concentration of 0.30 mmol/L. The obtained samples were characterized using field-emission scanning electron microscopy and transmission electron microscopy. The results indicated that left-handed twisted nanoribbons were obtained at pH=10.01, while straight nanoribbons were obtained at pH=7.15 and 12.34. The increasing of the aging time was beneficial to the formation of straight nanoribbons which should follow a dynamic templating approach. With increasing the mass ratio of TEOS/ L -18Phe6PyBr from 2 ∶ 1 to 15 ∶ 1, the width of the twisted nanoribbons increased and the helical pitch became longer. Silica tubular nanoribbons were obtained after removing the organic template by calcination. Silica prepared from TEOS/ L -18Phe6PyBr(2 ∶ 1, mass ratio) was used as the stationary phase of the gas chromatography for enantioseparation. The results indicated that 1-phenyl-1-propanol, 1-(4-chlorophenyl)ethanol and 2-methylpentanoic acid enantiomers were able to be separated. Chiral supramolecular imprinting was proposed to drive this enantiosepartion ability of the silica. The results not only gave us a better understanding of the cooperation self-assembly behavior of the silica oligomer and the low-molecular-weight gelator, but also brought out a chiral inorganic stationary phase for enantioseparation.

关 键 词：自组装 仿生矿化 二氧化硅 对映体拆分 气相色谱 

分 类 号：O631[理学—高分子化学]