硅胶表面霉酚酸分子印迹聚合物的合成及应用

Synthesis and application of mycophenolic acid-molecularly imprinted polymer based on silica gel surface

【目的】合成一种对霉酚酸具有特异性识别的分子印迹聚合物吸附材料,用于青贮饲料中霉酚酸的净化、富集和分析检测。【方法】以γ−甲基丙烯酰氧基丙基三甲氧基硅烷(γ-MPS)改性的硅胶为载体、霉酚酸酯为虚拟模板,合成硅胶表面接枝分子印迹聚合物,采用扫描电镜对制备材料进行表征,通过平衡吸附试验评价材料吸附特性。建立基于合成的分子印迹聚合物固相萃取−高效液相色谱(High performance liquid chromatography,HPLC)法检测青贮饲料中霉酚酸。【结果】改性硅胶表面成功包裹一层印迹聚合物。静态吸附试验表明,印迹材料饱和吸附量为4.5 mg/g;动态吸附试验表明,该材料吸附速率快,60 min内即达到吸附平衡。基于该印迹材料作为固相萃取吸附剂建立了HPLC法,霉酚酸的回收率为76.0%~81.2%,相对标准偏差小于7%,检测限达60μg/kg。【结论】制备的硅胶表面霉酚酸分子印迹聚合物可特异性吸附霉酚酸,建立的分子印迹聚合物固相萃取–HPLC法可用于日常青贮饲料中霉酚酸的分析测定,了解青贮饲料被霉菌毒素污染的状况。研究结果可为青贮饲料的质量安全控制提供指导。

【Objective】A molecularly imprinted polymer adsorbent with specific recognition for mycophenolic acid was synthesized for purification,enrichment and analysis of mycophenolic acid in silage.【Method】Using silica gel modified byγ-methacryloxy propyl trimethoxy silane(γ-MPS)as the carrier,mycophenolate mofetil as the virtual template,the surface molecularly imprinted polymers were prepared on silica gel.The prepared materials were characterized by scanning electron microscopy,and the adsorption characteristics were evaluated by equilibrium adsorption test.The solid phase extraction-high performance liquid chromatography(HPLC)method based on the synthesized molecularly imprinted polymer was established to detect the mycophenolic acid in silage.【Result】The modified silica gel surface was successfully wrapped with a layer of molecularly imprinted polymer.The static adsorption test showed that the saturated adsorption capacity of the imprinted material was 4.5 mg/g,and the dynamic adsorption test showed that the adsorption rate of the material was fast,and the adsorption equilibrium was reached within 60 min.The HPLC method was established using the imprinted material as the solid phase extraction adsorbent.The recovery rates of mycopholanolic acid were in the range of 76.0%to 81.2%,the relative standard deviation was less than 7%,and the detection limit was 60μg/kg.【Conclusion】The prepared mycophenolic acid molecularly imprinted polymer on the surface of silica gel can specifically adsorb mycophenolic acid.The established molecularly imprinted polymer solid phase extraction-HPLC method can be used for daily determination of mycophenolic acid in silage to know the situation of mycotoxin contamination in feed.The results can provide guidance for quality safety control of silage.