Lanthanide binding peptide surfactants at air–aqueous interfaces for interfacial separation of rare earth elements,Proceedings of the National Academy of Sciences of the United States of America

当前位置： X-MOL 学术 › Proc. Natl. Acad. Sci. U.S.A. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Lanthanide binding peptide surfactants at air–aqueous interfaces for interfacial separation of rare earth elements
Proceedings of the National Academy of Sciences of the United States of America ( IF 9.4 ) Pub Date : 2024-12-19 , DOI: 10.1073/pnas.2411763121
Luis E. Ortuno Macias, Felipe Jiménez-Ángeles, Jason G. Marmorstein, Yiming Wang, Stephen A. Crane, Surabh K. T., Pan Sun, Bikash Sapkota, Eshe Hummingbird, Woojin Jung, Baofu Qiao, Daeyeon Lee, Ivan J. Dmochowski, Robert J. Messinger, Mark L. Schlossman, Cesar de la Fuente-Nunez, Ravi Radhakrishnan, E. James Petersson, Monica Olvera de la Cruz, Wei Bu, Mrinal Bera, Binhua Lin, Raymond S. Tu, Kathleen J. Stebe, Charles Maldarelli

Rare earth elements (REEs) are critical materials to modern technologies. They are obtained by selective separation from mining feedstocks consisting of mixtures of their trivalent cation. We are developing an all-aqueous, bioinspired, interfacial separation using peptides as amphiphilic molecular extractants. Lanthanide binding tags (LBTs) are amphiphilic peptide sequences based on the EF-hand metal binding loops of calcium-binding proteins which complex selectively REEs. We study LBTs optimized for coordination to Tb 3+ using luminescence spectroscopy, surface tensiometry, X-ray reflectivity, and X-ray fluorescence near total reflection, and find that these LBTs capture Tb 3+ in bulk and adsorb the complex to the interface. Molecular dynamics show that the binding pocket remains intact upon adsorption. We find that, if the net negative charge on the peptide results in a negatively charged complex, excess cations are recruited to the interface by nonselective Coulombic interactions that compromise selective REE capture. If, however, the net negative charge on the peptide is −3, resulting in a neutral complex, a 1:1 surface ratio of cation to peptide is achieved. Surface adsorption of the neutral peptide complexes from an equimolar mixture of Tb 3+ and La 3+ demonstrates a switchable platform dictated by bulk and interfacial effects. The adsorption layer becomes enriched in the favored Tb 3+ when the bulk peptide is saturated, but selective to La 3+ for undersaturation due to a higher surface activity of the La 3+ complex.

更新日期：2024-12-19

点击分享查看原文

点击收藏

公开下载

阅读更多本刊新发论文本刊介绍/投稿指南