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Updated: Mar 20, 2026
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Synthesis of Cationized Magnetoferritin for Ultra-fast Magnetization of Cells
Published on: December 13, 2016
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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.
Nature Communications
|March 19, 2026
Summary
Researchers developed aptamers that change their binding to metal ions in strong magnetic fields. This magnetic field-induced binding modulation opens doors for new biosensing and therapeutic applications.
Area of Science:
- Biotechnology
- Biophysics
- Materials Science
Background:
- Modulating biological processes with magnetic fields is of significant interest.
- Aptamers offer precise molecular recognition capabilities.
Purpose of the Study:
- To develop aptamers with magnetically-modulated binding behavior for paramagnetic metal ions.
- To investigate the mechanisms underlying magnetic field-enhanced aptamer-metal ion interactions.
Main Methods:
- High-magnetic-field (HM)-SELEX (Systematic Evolution of Ligands by Exponential Enrichment) method was employed.
- Targeting cobalt ions (Co2+) under varying magnetic field strengths.
- Molecular simulations, chemical footprinting, and mutational analysis were used to elucidate mechanisms.
Main Results:
- Two classes of aptamers with distinct magnetically-modulated binding were identified.
- One aptamer class showed a 2-3 fold increase in affinity with increasing magnetic field strength.
- The second aptamer class exhibited a transition from minimal binding to significant affinity (~200 μM) at high magnetic fields (≥ 6 T).
- Molecular simulations indicated magnetic fields induce conformational changes by enhancing electrostatic interactions and optimizing nucleotide coordination.
Conclusions:
- The study successfully generated aptamers with magnetic field-responsive binding.
- These aptamers can function as 'aptamer switches' controlled by external magnetic fields.
- Potential applications include magnetic field-controlled biorecognition, biosensing, and therapeutics.
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