Nature can efficiently recognize specific ions by exerting second-sphere interactions onto well-folded protein scaffolds. However, a considerable challenge remains to artificially manipulate such affinity, while being cost-effective in managing immense amounts of water samples. Here, we propose an effective approach to regulate uranyl capture performance by creating bio-inspired nano-traps, illustrated by constructing chelating moieties into porous frameworks, where the binding motif’s coordinative interaction towards uranyl is enhanced by introducing an assistant group, reminiscent of biological systems. Representatively, the porous framework bearing 2-aminobenzamidoxime is exceptional in sequestering high uranium concentrations with sufficient capacities (530 mg g−1) and trace quantities, including uranium in real seawater (4.36 mg g−1, triple the benchmark). Using a combination of spectroscopic, crystallographic, and theory calculation studies, it is revealed that the amino substituent assists in lowering the charge on uranyl in the complex and serves as a hydrogen bond acceptor, boosting the overall uranyl affinity of amidoxime.
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机译:大自然可以通过在折叠良好的蛋白质支架上施加第二球相互作用来有效识别特定离子。然而,在人为地操纵这种亲和力的同时,在管理大量水样品方面要具有成本效益,这仍然是一个巨大的挑战。在这里,我们提出了一种有效的方法,通过创建生物启发性的纳米陷阱来调节铀酰的捕获性能,例如通过将螯合部分构建到多孔框架中来说明,其中通过引入一个助手基团增强了结合基序与铀酰的协调相互作用,让人联想到生物系统。具有代表性的是,带有2-氨基苯甲酰胺肟的多孔骨架在螯合高铀浓度,具有足够的容量(530 mg g -1 sup>)和微量(包括真实海水中的铀)(4.36 mg g - 1 sup>,将基准提高三倍)。结合光谱学,晶体学和理论计算研究,发现氨基取代基有助于降低络合物中铀酰的电荷并充当氢键受体,从而提高了a肟的总体铀酰亲和力。
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