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Martini Force Field for Protonated Polyethyleneimine
Titus Adrian Beu1, Andrada-Elena Ailenei1, Răzvan-Ioan Costinaş1
1Faculty of Physics, Department of Biomolecular Physics, University Babeş-Bolyai, Mihail Kogălniceanu Street 1, Cluj-Napoca, 400084, Romania.
Journal of Computational Chemistry
|November 26, 2019
Summary
Researchers developed a new coarse-grained force field for polyethyleneimine (PEI), a key nonviral gene carrier. This model enables large-scale simulations of DNA-PEI complexes, advancing gene delivery research.
Area of Science:
- Computational Chemistry
- Polymer Science
- Biophysics
Background:
- Polyethyleneimine (PEI) is a widely used nonviral gene carrier.
- Accurate simulation of PEI behavior is crucial for understanding gene delivery mechanisms.
- Existing models may not fully capture the dynamic structural features of protonated PEI.
Purpose of the Study:
- To develop a realistic coarse-grained (CG) force field (FF) for protonated PEI.
- To enable large-scale simulations of DNA-PEI complex formation and condensation.
- To accurately reproduce dynamic structural features of PEI chains.
Main Methods:
- Parametrization of CG Martini FF models for PEI in polarizable and nonpolarizable water.
- Application of Boltzmann inversion techniques to all-atom (AA) probability distributions.
- Fine-tuning FFs by fitting simulated CG gyration radii and end-to-end distances to AA counterparts.
Main Results:
- Developed well-suited Martini FF models for PEI.
- Demonstrated the models' ability to reproduce dynamic structural features.
- Validated the models against all-atom simulations for accuracy.
Conclusions:
- The developed CG Martini FF models are effective for large-scale simulations of PEI.
- These models can accurately predict size/protonation-dependent behavior of solvated PEI chains.
- The FF enables realistic simulations of DNA-PEI systems for gene delivery applications.
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