Abstract A novel fluorescent sensor of tryptophan functionalized mesoporous silica (Trp-Meso-Si) for detecting Zn2+ ion was designed by modifying the framework of nanoporous material with Tryptophan organic silicon source under the template via co-condensation method. Tryptophan organic silicon source was first synthesized by selecting natural amino acid as reagent via multi-steps reactions. The sensing material Trp-Meso-Si was well characterized by various spectroscopic techniques. The results indicate that material 5%-Trp-Meso-Si with low amounts of Tryptophan exhibits well-ordered one-dimensional hexagonal P6mm structure. However, the sample 15%-Trp-Meso-Si with high amounts of Tryptophan shows strongest fluorescent intensity at the same excited wavelength of 285 nm. All the materials Trp-Meso-Si indicate fluorescent signal at excited wavelength because of tryptophan as fluorophore moiety. In the fluorescent recognition experiments, Trp-Meso-Si could selectively and sensitively detect trace concentrations of Zn2+ ions in aqueous solution with satisfactory detection limits of 0.9 × 10-7M. Tryptophan within the framework of mesoporous silica material showed strong affinity for Zn2+ ions according to a 3:1 ratio of [tryptophan] and [Zn2+] by plenty of groups with lone pair electrons.

中文翻译：

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纳米多孔材料的色氨酸功能化框架作为用于痕量 Zn2+ 离子检测的荧光传感器

摘要 以色氨酸有机硅源为模板，通过共缩合法对纳米多孔材料的骨架进行修饰，设计了一种新型色氨酸功能化介孔二氧化硅（Trp-Meso-Si）荧光传感器，用于检测Zn2+离子。色氨酸有机硅源是首先选择天然氨基酸为试剂，通过多步反应合成的。传感材料 Trp-Meso-Si 通过各种光谱技术得到了很好的表征。结果表明，具有少量色氨酸的 5%-Trp-Meso-Si 材料表现出有序的一维六边形 P6mm 结构。然而，具有大量色氨酸的 15%-Trp-Meso-Si 样品在 285 nm 的相同激发波长下显示出最强的荧光强度。由于色氨酸作为荧光团部分，所有材料 Trp-Meso-Si 都在激发波长下显示荧光信号。在荧光识别实验中，Trp-Meso-Si 可以选择性、灵敏地检测水溶液中痕量浓度的 Zn2+ 离子，检测限为 0.9 × 10-7M。根据 [色氨酸] 和 [Zn2+] 的 3:1 比例，介孔二氧化硅材料框架内的色氨酸通过大量具有孤对电子的基团显示出对 Zn2+ 离子的强亲和力。