分子印迹光子晶体传感芯片的制备及对邻苯二甲酸酯类化合物的检测

Preparation of Molecular Imprinted Photonic Crystal Sensor and Its Application in Determination of Phthalate Esters

将光子晶体与分子印迹技术相结合,制备了一种反蛋白石结构的分子印迹光子晶体传感芯片,并将其应用于4种邻苯二甲酸酯类化合物的检测效果研究。分子印迹光子晶体传感芯片的制备过程包含3个步骤。首先,通过垂直沉降自组装方法制备Si O2蛋白石结构模版;随后,向蛋白石结构模板空隙中填充含有印迹分子邻苯二甲酸二异壬酯（DINP）的预聚液,引发光聚合;最后,移除Si O2结构模版及印迹分子,得到对邻苯二甲酸酯类化合物具有特异性识别功能的分子印迹光子晶体传感芯片。结果表明,传感芯片对待测物分子的识别过程可通过布拉格方程转换为可读的光学信号,当4种待测物浓度从1×10^-5mol/L增大到1 mol/L时,最大衍射峰位置发生20-40 nm的红移,且检测过程仅需6 min。检测芯片高度交联的聚合物结构令其具有较高的稳定性和重复利用性,5次检测后,芯片仍保持较好的传感性能。

In this work,an inverse opal structural molecular imprinted photonic crystal（ MIPC） sensor was developed and its efficiency on determination of four phthalate esters was investigated. The preparation of MIPC consisted of three steps. Firstly,an opal structure was obtained by vertical deposition self-assembly of monodisperse Si O2 nanospheres. Then,polymerization was performed through filling the interspace of Si O2 nanospheres with acrylamide（ AM） and methacrylic acid（ MAA） as co-monomer and diisononyl phthalate（ DINP） as imprinting molecule. Finally,MIPC was obtained after removing Si O2 nanospheres and imprinting molecule from polymer. Scanning electron microscope showed that the MIPC possessed a highly ordered threedimensional macroporous structure with abundant nanocavities. The recognition of target analytes could be directly transferred into readable optical signals through a change in Bragg diffraction of the ordered macropores array of MIPC. The results showed that the maximum Bragg diffraction peak red-shifted 20- 40 nm when the concentration of phthalate esters changed from 1 × 10^-5mol / L to 1 mol / L. The response time of MIPC was within 6 min,and the MIPC could be used for at least 5 times due to the excellent stability of highly crosslinked polymer.