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Updated: May 2, 2026

A Method for Selecting Structure-switching Aptamers Applied to a Colorimetric Gold Nanoparticle Assay
Published on: February 28, 2015
Reducing binding site heterogeneity via truncation of the RTX domain enhances selectivity for rare earth element
Farid F Khoury1, Sameera Abeyarthna1, Bradley S Heater2
1Department of Chemical Engineering, Columbia University, New York, NY 10027, USA. sb2373@columbia.edu.
Abstract:
Rare earth elements (REEs) are critical components of modern technologies but present a notoriously difficult separation challenge. Here, we report a rationally truncated variant of the calcium-binding RTX domain that improves REE selectivity by reducing binding site heterogeneity. The engineered scaffold, RTX(2), exhibits improved binding affinity, structure stability, pH-tunable elution, and enhanced chromatographic resolution, achieving over 200-fold selectivity within the REE series.
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