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Updated: Jul 13, 2026
08:30
Gene-therapy Inspired Polycation Coating for Protection of DNA Origami Nanostructures
Published on: January 19, 2019
Complexation of DNA with cationic gemini surfactant in aqueous solution
Xiaofang Zhao1, Yazhuo Shang, Honglai Liu
1The State Key Laboratory of Chemical Engineering and Department of Chemistry, East China University of Science and Technology, Shanghai 200237, China.
Journal of Colloid and Interface Science
|July 17, 2007
Summary
Cationic gemini surfactants effectively neutralize DNA
Area of Science:
- Biochemistry
- Physical Chemistry
- Materials Science
Background:
- DNA's negative charge facilitates interactions with cationic molecules.
- Gemini surfactants are a class of molecules with unique properties due to their dual cationic head groups.
- Understanding DNA-surfactant interactions is crucial for drug delivery and gene therapy applications.
Purpose of the Study:
- To investigate the interactions between DNA and a specific gemini surfactant (12-3-12).
- To characterize the formation and properties of DNA-gemini surfactant complexes.
- To elucidate the influence of salt concentration on these interactions.
Main Methods:
- UV-vis transmittance spectroscopy.
- Zeta potential measurements.
- Fluorescence emission spectroscopy using pyrene and ethidium bromide (EB).
Main Results:
- Effective neutralization of DNA's negative charges by the cationic gemini surfactant.
- Formation of DNA-induced micelle-like structures of the surfactant.
- Critical aggregation concentration (CAC) showed minimal dependence on sodium bromide (NaBr) concentration.
- NaBr at high concentrations promoted larger DNA/surfactant aggregates.
- Strong cooperative binding between surfactant and DNA was evidenced by ethidium bromide displacement.
Conclusions:
- Gemini surfactants can effectively bind and neutralize DNA.
- The binding is cooperative and influenced by salt concentration.
- These findings have implications for the design of novel DNA-based materials and delivery systems.
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