CAS Key Laboratory of Engineering Plastics, CAS Research/Education Center for Excellence in Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences (CAS) , Beijing 100190, China.
University of Chinese Academy of Sciences , Beijing 100049, China.
ACS Appl Mater Interfaces. 2018 Jan 17;10(2):2114-2121. doi: 10.1021/acsami.7b17342. Epub 2018 Jan 2.
Iron ions play a vital role in many biological processes, and their concentrations are responsible for human health. Therefore, it is essential to detect the concentration of iron ions by a rapid, accurate, highly selective, and practical method. Herein, we have synthesized a cellulose-based fluorescent sensor (Phen-MDI-CA) for the highly selective and rapid detection of Fe ions via chemically bonding 1,10-phenanthroline-5-amine (Phen) onto cellulose acetate (CA) using 4,4'-methylene diphenyl diisocyanate (MDI) as a cross-linker. Benefiting from the anchoring and diluting effect of a cellulose skeleton, the resultant Phen-MDI-CA displays excellent fluorescence properties in both solution and solid state. More interestingly, a cellulose-based polymer chain significantly improves the sensitivity of phenanthroline to Fe ions. Upon meeting Fe ions, a red, insoluble, and nonfluorescent Fe-(Phen-MDI-CA) complex appears immediately; thus, Phen-MDI-CA can work as a multimode chromogenic sensor for the highly selective, sensitive, and rapid detection of Fe ions. In the instrument-free visual mode, the detection limit for Fe ions is 50 ppb, and in fluorescence mode, the detection limit is 2.6 ppb. To our knowledge, this is the first time that such a low detection limit for Fe ions in aqueous media has been observed by the naked eye. In addition, Phen-MDI-CA has good solubility and processability in common organic solvents, which facilitates its use in different material forms, e.g., printing ink, coating, and film. Therefore, the Fe-responsive and chromogenic Phen-MDI-CA exhibits a huge potential in the detection and extraction of Fe ions.
铁离子在许多生物过程中起着至关重要的作用，其浓度关系到人类健康。因此，用一种快速、准确、高选择性和实用的方法来检测铁离子的浓度是至关重要的。在这里，我们通过化学键合 1,10-菲啰啉-5-胺（Phen）到醋酸纤维素（CA）上，使用 4,4'-亚甲基二苯基二异氰酸酯（MDI）作为交联剂，合成了一种基于纤维素的荧光传感器（Phen-MDI-CA），用于通过化学键合 1,10-菲啰啉-5-胺（Phen）到醋酸纤维素（CA）上来实现对 Fe 离子的高选择性和快速检测。受益于纤维素骨架的锚固和稀释作用，所得 Phen-MDI-CA 在溶液和固态中均表现出优异的荧光性能。更有趣的是，基于纤维素的聚合物链显著提高了菲啰啉对 Fe 离子的灵敏度。遇到 Fe 离子时，立即出现红色、不溶和非荧光的 Fe-(Phen-MDI-CA)配合物；因此，Phen-MDI-CA 可以作为一种多模式比色传感器，用于 Fe 离子的高选择性、高灵敏度和快速检测。在无仪器的目视模式下，Fe 离子的检测限为 50ppb，在荧光模式下，检测限为 2.6ppb。据我们所知，这是首次通过肉眼观察到在水介质中如此低的 Fe 离子检测限。此外，Phen-MDI-CA 在常见有机溶剂中具有良好的溶解性和加工性，这有助于其在不同的材料形式中使用，例如油墨、涂层和薄膜。因此，对 Fe 有响应且显色的 Phen-MDI-CA 在 Fe 离子的检测和提取方面具有巨大的潜力。
