松脂素二糖苷印迹修饰金属有机骨架复合材料的合成及其吸附性能

构建了金属有机骨架MIL-101的后合成印迹修饰法以改善其对松脂素二糖苷(PDG)的吸附选择性。MIL-101经过氨基化修饰及表面接枝制备了金属有机骨架-分子印迹复合材料MIPs@ED-MIL-101,用X射线衍射法、红外光谱法及扫描电镜分析对MIL-101的晶体结构、表面化学功能基团及结构形貌进行表征。测试了MIPs@ED-MIL-101对模板分子的吸附动力学、选择性及固相萃取性能。结果表明,经印迹修饰后的MIL-101对PDG的吸附性能大幅提高,且对模拟混合物中的PDG也具有较高的竞争吸附选择性。当以MIPs@ED-MIL-101为吸附剂从杜仲提取物中提取和分离PDG时,产品纯度85.3%,且复合材料多次重复使用后对目标化合物的吸附量变化不大。

Synthesis and Adsorption Performance of Pinoresinol Diglucoside Imprint-Modified Metal Organic Frame Composites

A novel post-synthetic modification method for metal organic frames MIL-101 was constructed to improve its rebinding selectivity in separation and analysis field. A MIL-101-molecular imprint composite material named as MIPs@ED-MIL-101 can be obtained by ethylene diamine modification and surface graft of pinoresinol?diglucoside (PDG) imprinted polymers. X-Ray Diffraction (XRD), fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were used to monitor this synthesis procedure in crystal structure, surface chemical group and particle morphology. This composite material was suffered from performance tests including adsorption dynamics, adsorption selectivity, extraction application and so on. Results indicated a high improvement for this novel material in the adsorption dynamics and adsorption capacity, with a 30% decreasing in adsorption equilibrium time and a 42.5% increase in saturated adsorption capacity. Especially, the selectivity for this material toward target PDG has increased 38.5 and 75.6%, with a selectivity factor of 1.695 and 1.918 (relative to medioresinol diglucoside and syringaresinol diglucoside). Besides, a high competitive adsorption selectivity for this MIPs@ED-MIL-101 composite material can also be observed. Scatchard analysis indicated three types of binding sites in this composite material while there was only one type sites in the MIL-101. When this MIPs@ED-MIL-101 composite material was used as adsorbent for the extraction and separation of PDG from crude extract of Eucommia ulmoides, it exhibited high application ability. Also, this novel material can also be reused for many times with a slight loss in adsorption capacity.