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Updated: Mar 20, 2026
Synthesis of Cationized Magnetoferritin for Ultra-fast Magnetization of Cells
Published on: December 13, 2016
Aptamers with magnetically tunable affinity for divalent cobalt ions
Shengjie Gao1, Lu Wang2,3, Lili Yao1
1School of Food and Biological Engineering, Hefei University of Technology, Hefei, China.
Abstract:
There is considerable interest in the ability to modulate biological processes with magnetic fields. Here we demonstrate a strategy for selecting aptamers that exhibit enhanced binding to paramagnetic metal ions under a strong magnetic field. Using a high-magnetic-field (HM)-SELEX method targeting Co2+, we identified two classes of aptamers with magnetically-modulated binding behavior. One displayed a gradual 2-3-fold increase in affinity as magnetic field strength increased, while the other went from minimal target binding at ambient field strength to an affinity of ~200 μM at ≥ 6 T. Molecular simulations revealed that the magnetic field induces a global conformational rearrangement by enhancing aptamer-metal electrostatic interactions, optimizing the coordination geometry of the nucleotides. Chemical footprinting and mutational analysis confirmed the role of certain conformational changes in magnetically-induced ion binding. These results suggest opportunities to generate aptamer switches that can be used to manipulate biorecognition processes via an externally applied magnetic field in diverse applications.
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