Biosensor and Materials Group, Korea Institute of Science and Technology Europe, Universität des Saarlandes Campus E7 1, 66123, Saarbrücken, Germany.
Department of Chemistry, College of Natural Science, Soongsil University, Seoul, 06978, Republic of Korea.
Sci Rep. 2019 Jul 16;9(1):10293. doi: 10.1038/s41598-019-46881-7.
In this study, we synthesized molecularly imprinted mesoporous organosilica (MIMO) in the presence of a new precursor having a zwitterionic functional group and an imprint molecule, namely, glyphosate (MIMO-z). The precursor-glyphosate complex engaged in a typical base-catalyzed sol-gel reaction and the introduced zwitterion group remained intact in the framework after the extraction process had been completed. To test the rebinding performance of the target molecule, graphene quantum dots were encapsulated (MIMO-zQ) into pores and the fluorescence intensity change was monitored according to the concentration of glyphosate. When the MIMO-zQ suspension was diluted into the glyphosate solutions, notable fluorescence quenching occurred, right down to sub-nanomolar levels of concentration; 9.2 ± 0.18% quenching at 0.1 nM (0.017 ppb, 17 pg/mL). This result is one of the best reported to date for sensing using MIMO. The synthesized probe also exhibited a distinct signal compared to a series of competing compounds, aminomethylphosphonic acid and glycine; 4.3 ± 0.019% and 3.7 ± 0.041% quenching at 100 nM.
在这项研究中，我们在存在具有两性离子官能团和印迹分子草甘膦的新型前体的情况下合成了分子印迹介孔有机硅（MIMO）。前体-草甘膦复合物参与了典型的碱催化溶胶-凝胶反应，并且在萃取过程完成后，引入的两性离子基团在骨架中保持完整。为了测试目标分子的再结合性能，将石墨烯量子点封装（MIMO-zQ）到孔中，并根据草甘膦的浓度监测荧光强度变化。当 MIMO-zQ 悬浮液稀释到草甘膦溶液中时，会发生明显的荧光猝灭，直至亚纳摩尔浓度；在 0.1 nM（0.017 ppb，17 pg/mL）时猝灭率为 9.2±0.18%。这一结果是目前使用 MIMO 进行传感的最佳结果之一。与一系列竞争化合物氨基甲基膦酸和甘氨酸相比，合成的探针也表现出明显的信号；在 100 nM 时猝灭率分别为 4.3±0.019%和 3.7±0.041%。
