Conclusions
The stability of the ionic complexes formed between plasmid DNA and chitosan self-aggregates was investigated by testing the reversibility of the complex formation using anionic polymers. Complexes formed between plasmid DNA and chitosan self-aggregates appeared to be far more stable against anionic exchange reactions, compared with complexes formed between plasmid DNA and Lipofectamine®, although both complexes had the same charge ratios. This approach to testing the stability of DNA/polycation complexes may be critical in designing novel non-viral gene delivery systems.