Wang Jin, Kaiyum Yunus A, Li Xiangmei, Lei Hongtao, Johnson Philip E, Liu Juewen
Guangdong Provincial Key Laboratory of Food Quality and Safety, College of Food Science, South China Agricultural University, Guangzhou 510642, China.
Department of Chemistry, Waterloo Institute for Nanotechnology, University of Waterloo, Waterloo, Ontario N2L 3G1, Canada.
J Am Chem Soc. 2025 Jan 15;147(2):1831-1839. doi: 10.1021/jacs.4c13768. Epub 2025 Jan 1.
Rare earth elements (REEs) are widely used in various high-tech industries. Developing affinity ligands that can detect and distinguish REEs is at the forefront of analytical chemistry. It is also interesting to understand the limits of natural biomolecules for the recognition of REEs. In this study, Sc was used as a target for the isolation of DNA aptamers, and an aptamer named Sc-1 was obtained. Using a thioflavin T (ThT) fluorescence assay, Sc-1 bound only to REEs, but not other metal ions. Additionally, the binding of Sc-1 to Sc exhibited slow kinetics, and the binding complex resisted dissociation by EDTA. Furthermore, Sc-1 displayed varying binding kinetics with trivalent lanthanide ions, allowing for the discrimination of 17 REEs into three major groups: (1) La, Ce, Pr, Nd, Sm, Eu, and Gd; (2) Tb, Dy, Ho, Er, Tm, Yb, Lu, and Y; and (3) Sc. NMR spectroscopy confirmed binding-induced conformational changes in the aptamer. Using the fluorescence strand-displacement method, the true of the aptamer was measured to range from 0.6 to 258.5 nM for the REE ions, and it showed effective detection of Sc in real samples.
稀土元素（REEs）广泛应用于各种高科技产业。开发能够检测和区分稀土元素的亲和配体是分析化学的前沿领域。了解天然生物分子识别稀土元素的局限性也很有趣。在本研究中，将钪（Sc）用作分离DNA适配体的目标，获得了一种名为Sc-1的适配体。使用硫黄素T（ThT）荧光测定法，Sc-1仅与稀土元素结合，而不与其他金属离子结合。此外，Sc-1与钪的结合动力学缓慢，且结合复合物能抵抗乙二胺四乙酸（EDTA）的解离。此外，Sc-1与三价镧系离子表现出不同的结合动力学，可将17种稀土元素分为三大类：（1）镧（La）、铈（Ce）、镨（Pr）、钕（Nd）、钐（Sm）、铕（Eu）和钆（Gd）；（2）铽（Tb）、镝（Dy）、钬（Ho）、铒（Er）、铥（Tm）、镱（Yb）、镥（Lu）和钇（Y）；（3）钪（Sc）。核磁共振光谱证实了适配体中结合诱导的构象变化。使用荧光链置换法，测得该适配体对稀土离子的真实解离常数范围为0.6至258.5 nM，并且它在实际样品中显示出对钪的有效检测。
