Department of Chemistry and Institute for Biophysical Dynamics, The University of Chicago, Illinois 60637, USA.
Inorg Chem. 2011 Sep 5;50(17):7937-9. doi: 10.1021/ic201094e. Epub 2011 Aug 5.
The separation of lanthanides from minor actinides such as americium and curium is an important step during the recycling process in the treatment of nuclear waste. However, the similar chemistry and ionic size of lanthanide and actinide ions make the separation challenging. Here, we report that a peptide-based reagent can selectively bind trivalent actinides over trivalent lanthanides by means of introducing soft-donor atoms into a peptide known as a lanthanide-binding tag (LBT). Fluorescence spectroscopy has been used to measure the dissociation constant of each metal/peptide complex. A 10-fold selectivity was obtained for Am(3+) over the similarly sized lanthanide cation, Nd(3+), when the asparagine on the fifth position of a LBT was mutated to a cysteine and further functionalized by a pyridine moiety.
从核废料处理的再循环过程中，将镧系元素与锕系元素（如镅和锔）等少量的锕系元素分离是一个重要的步骤。然而，镧系元素和锕系元素离子的化学性质和离子半径相似，使得分离具有挑战性。在这里，我们报告了一种基于肽的试剂，通过在一种被称为镧系元素结合标签（LBT）的肽中引入软给体原子，可以选择性地结合三价锕系元素而不是三价镧系元素。荧光光谱法已被用于测量每个金属/肽复合物的离解常数。当 LBT 第五位的天冬酰胺突变为半胱氨酸，并进一步用吡啶部分官能化时，与同样大小的镧系阳离子 Nd(3+)相比，Am(3+)的选择性提高了 10 倍。
