Related Experiment Video
Updated: Jul 17, 2026
06:13
Electroeluting DNA Fragments
Published on: September 5, 2010
In vitro evolution of functional DNA using capillary electrophoresis
Shaun D Mendonsa1, Michael T Bowser
1Department of Chemistry, University of Minnesota, 207 Pleasant Street SE, Minneapolis, Minnesota 55455, USA.
Journal of the American Chemical Society
|January 8, 2004
Summary
This study introduces capillary electrophoresis-SELEX (CE-SELEX), a novel method for isolating aptamers. CE-SELEX offers a bias-free selection process in free solution, yielding functional nucleic acid sequences efficiently.
Area of Science:
- Biochemistry
- Molecular Biology
- Analytical Chemistry
Background:
- Systematic evolution of ligands by exponential enrichment (SELEX) is a powerful technique for identifying functional nucleic acid sequences (aptamers).
- Conventional SELEX methods, often relying on affinity chromatography, can introduce kinetic and immobilization biases during the selection process.
- These biases stem from slow elution kinetics and the requirement for target molecules to be tethered to a support, deviating from free solution conditions.
Purpose of the Study:
- To develop and validate a novel SELEX approach utilizing capillary electrophoresis (CE) for aptamer selection.
- To eliminate biases associated with conventional SELEX methods by performing selection in free solution.
- To demonstrate the efficacy of CE-SELEX by selecting anti-immunoglobulin E (IgE) aptamers.
Main Methods:
- The study employed a novel CE-SELEX technique, integrating capillary electrophoresis with the SELEX process.
- Selection was performed in free solution, allowing target-binding nucleic acid sequences to exhibit a mobility shift.
- Separation of functional aptamers from non-binding sequences was achieved based on differential migration rates in the capillary.
- Kinetic bias was eliminated by avoiding the need to elute bound sequences from a stationary phase.
Main Results:
- The CE-SELEX method successfully demonstrated its viability for aptamer isolation.
- High-affinity anti-IgE aptamers were obtained after only two rounds of selection.
- The selected aptamers exhibited dissociation constants as low as 40 nM, indicating high binding affinity.
Conclusions:
- CE-SELEX represents a significant advancement in aptamer selection technology.
- This method provides a bias-free and efficient alternative to conventional SELEX techniques.
- The successful selection of potent anti-IgE aptamers validates the utility of CE-SELEX for generating high-affinity nucleic acid ligands.
