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Effects of Control Factors on Protein-Polyelectrolyte Complex Coacervation
Jin Zhou1, Yuting Wan1, Martien A Cohen Stuart1
1State-Key Laboratory of Chemical Engineering, and Shanghai Key Laboratory of Multiphase Materials Chemical Engineering, East China University of Science and Technology, 130 Meilong Road, 200237, Shanghai, People's Republic of China.
Biomacromolecules
|November 13, 2023
Summary
Controlling protein-polyelectrolyte coacervation is key for mimicking cell organization. This study reveals how pH, ionic strength, and polymer structure influence coacervation, ensuring safe protein encapsulation without altering structure or activity.
Area of Science:
- Biomaterials Science
- Polymer Chemistry
- Biophysics
Background:
- Protein-polyelectrolyte complex coacervation mimics intracellular phase separation.
- Protein structure and charge distribution pose challenges in regulating coacervation.
Purpose of the Study:
- Investigate factors controlling protein-polyelectrolyte coacervation.
- Understand the effects of polymer properties on coacervation.
- Assess the impact of coacervation on protein structure and activity.
Main Methods:
- Prepared mixtures of bovine serum albumin (BSA) with various cationic polymers (linear and branched).
- Varied pH, ionic strength, polymer chain length, charge groups, and structure.
- Analyzed coacervate formation, complexation, and protein integrity.
Main Results:
- Moderate pH and ionic strength are crucial for coacervate droplet formation.
- Excess polyelectrolytes are often needed for full complexation, deviating from charge stoichiometry.
- Longer chains, primary amine groups, and branched polymers enhance electrostatic interaction and lead to solid-like complexes.
- Coacervation did not disrupt BSA structure or activity, indicating safe protein encapsulation.
Conclusions:
- Diverse factors critically control protein-polyelectrolyte coacervation.
- Established principles guide the development of protein-based coacervations for applications.
- Coacervation offers a safe method for encapsulating proteins without compromising their function.
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