Compliant Clients: Catechols Exhibit Enhanced Solubility and Stability in Diverse Complex Coacervates.

Area of Science:

• Materials Science
• Physical Chemistry
• Biomaterials

Background:

• Polyelectrolyte coacervates are versatile materials with unique properties like high density and shear-thinning viscosity.
• Their metastability and lack of analytical methods hinder the study of their attributes as solvent media.
• Understanding coacervates' interactions with small molecules is crucial for material fabrication and biological applications.

Purpose of the Study:

• To investigate the behavior of low-molecular-weight catechols within polyelectrolyte coacervate phases.
• To explore the potential of coacervates as specialized solvent media for redox-active molecules.
• To gain insights into the molecular interactions governing coacervate-solute systems.

Main Methods:

• Utilized solution electrochemistry to analyze redox potentials.
• Employed nuclear magnetic resonance (NMR) spectroscopy to study molecular interactions.
• Prepared and characterized polyelectrolyte coacervate dispersions.

Main Results:

• Catechols preferentially partitioned into the coacervate phase, with concentrations up to 260-fold higher than in the equilibrium solution.
• Coacervates significantly stabilized catechol redox potentials, shifting them by up to +200 mV.
• Demonstrated a distinct interaction between phase-separated polyelectrolytes and catechols compared to aqueous solutions.

Conclusions:

• Polyelectrolyte coacervates act as effective media for concentrating and stabilizing redox-unstable molecules like catechols.
• The observed preferential partitioning and redox stabilization highlight unique solute-solvent interactions within coacervates.
• These findings suggest potential applications in insulating and preserving sensitive chemicals.