Effect of ligand alkyl chain length on lanthanide extraction using liposomes incorporating diglycolamic acid

IF 2 4区化学 Q3 CHEMISTRY, ANALYTICAL

Analytical Sciences Pub Date : 2026-03-13 DOI:10.1007/s44211-026-00889-y

Takeru Uehara, Shinya Yamasaki, Sota Shimizu, Yuichi Takaku, Yudai Shigekawa, Aya Sakaguchi

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Abstract

This study introduces an environmentally benign liposome-based extraction system that selectively separates and recovers lanthanides (Ln) without requiring an organic solvent. Recovery of Ln, particularly from high-level radioactive liquid waste streams, is critical for resource utilization and reducing long-term radiotoxicity. The proposed system incorporates highly Ln-selective diglycolamic acid (DGAA) ligands into phospholipid liposomes. Fluorescence spectroscopy demonstrated that europium (Eu) adsorption, mediated by the hydrophilic head group of the incorporated DGAA ligands, reached equilibrium almost immediately upon mixing. Inductively coupled plasma–mass spectrometry revealed that the adsorption efficiency increased with increasing concentration of incorporated DGAA. Approximately three DGAA ligands are required to adsorb one Eu(III) ion. The selectivity for heavy Ln was comparable to that of conventional DGAA-based solvent-extraction systems and was found to be independent of DGAA alkyl chain length. In contrast, the incorporation stability depended on alkyl chain length; for example, liposomes containing N,N-didodecyldiglycolamic acid retained the ligand without significant precipitation or fluorescence decrease for 7 days at concentrations up to 237 µM/g-egg lecithin. These findings establish liposome-based extraction as a flexible platform in which the ligand head group governs the adsorption characteristics while the alkyl chain length dictates the incorporation stability, providing a quantitative foundation for future solvent-free separation technologies.

Graphical abstract

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配体烷基链长度对二乙醇酸脂质体萃取镧系元素的影响。

本研究介绍了一种环境友好的基于脂质体的萃取系统，该系统可以选择性地分离和回收镧系元素（Ln），而不需要有机溶剂。回收Ln，特别是从高放射性废液流中回收，对于资源利用和减少长期放射性毒性至关重要。该系统将高选择性二乙醇酸（DGAA）配体整合到磷脂脂质体中。荧光光谱表明，在掺入的DGAA配体的亲水性头基的介导下，铕（Eu）的吸附在混合后几乎立即达到平衡。电感耦合等离子体质谱分析表明，吸附效率随掺入DGAA浓度的增加而增加。大约需要三个DGAA配体来吸附一个Eu（III）离子。对重Ln的选择性与传统的DGAA溶剂萃取体系相当，并且与DGAA烷基链长度无关。相反，掺入稳定性与烷基链长度有关；例如，含有N，N-二十二烷基二甘醇酸的脂质体在237 μ M/g卵磷脂浓度下保留配体7天，没有明显的沉淀或荧光下降。这些发现确立了脂质体萃取是一个灵活的平台，其中配体头基决定吸附特性，而烷基链长度决定掺入稳定性，为未来的无溶剂分离技术提供了定量基础。

本文章由计算机程序翻译，如有差异，请以英文原文为准。

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来源期刊

Analytical Sciences 化学-分析化学

CiteScore

2.90

自引率

18.80%

发文量

232

审稿时长

1 months

期刊介绍： Analytical Sciences is an international journal published monthly by The Japan Society for Analytical Chemistry. The journal publishes papers on all aspects of the theory and practice of analytical sciences, including fundamental and applied, inorganic and organic, wet chemical and instrumental methods. This publication is supported in part by the Grant-in-Aid for Publication of Scientific Research Result of the Japanese Ministry of Education, Culture, Sports, Science and Technology.