Coacervate microenvironments modulate fluorescent dye behaviour and Förster energy transfer dynamics

Area of Science:

• Materials Science
• Supramolecular Chemistry
• Photophysics

Background:

• Coacervates are liquid-liquid phase separated systems formed by oppositely charged polymers.
• They create unique microenvironments that can influence molecular behavior.
• Understanding these environments is key to designing functional materials.

Purpose of the Study:

• To investigate how complex coacervates affect the photophysical properties of encapsulated dyes.
• To explore the potential of coacervates as templates for nanoscale photonic and energy-transfer materials.

Main Methods:

• Formation of complex coacervates using poly-L-lysine and anionic fluorophores.
• Characterization of dye photophysical properties (fluorescence, energy transfer) within the coacervate microenvironment.
• Analysis of the interplay between dye loading, local enrichment, and aggregation.

Main Results:

• Coacervate microenvironment modulates dye fluorescence, showing enhancement at low concentrations and quenching at high concentrations due to aggregation.
• Efficient energy transfer was observed between dye molecules within the coacervates.
• The observed effects are attributed to competing influences of local enrichment and aggregation.

Conclusions:

• Complex coacervates provide tunable environments for controlling molecular photophysics.
• Coacervates serve as versatile platforms for developing adaptive nanoscale photonic and energy-transfer materials.
• These findings open avenues for designing novel smart materials with tailored optical properties.