Aging mechanisms of perfluorocarbon emulsions using image analysis

Area of Science:

• Colloid and Surface Science
• Materials Science
• Biomedical Engineering

Background:

• Perfluorocarbon (PFC) emulsions are crucial in biomedical applications, such as oxygen carriers and contrast agents.
• Understanding the aging mechanisms of PFC emulsions is vital for ensuring their long-term stability and efficacy.
• Previous studies have focused on specific factors, but a comprehensive investigation of multiple parameters is needed.

Purpose of the Study:

• To investigate the aging mechanisms of oil-in-water perfluorocarbon emulsions.
• To evaluate the influence of emulsifiers, temperature, and aqueous phase composition on emulsion stability.
• To determine the dominant aging pathways, namely coalescence and molecular diffusion.

Main Methods:

• Preparation of n-perfluorohexane and perfluorodecalin emulsions using Lecithin, Span 20, and Pluronic F-68.
• Sonication technique employed for emulsion preparation.
• Stability assessment through droplet size analysis over time under varying temperatures and aqueous media (water vs. microbial culture medium).

Main Results:

• Emulsion stability is significantly influenced by all investigated parameters: emulsifier type, temperature, and aqueous phase composition.
• Both coalescence and molecular diffusion were identified as aging mechanisms.
• Analysis revealed that coalescence is more prevalent than previously reported and is accelerated by increased temperature.

Conclusions:

• The stability of perfluorocarbon emulsions is a complex interplay of various factors.
• Coalescence emerges as a dominant aging mechanism, particularly at elevated temperatures.
• These findings provide critical insights for the formulation and storage of stable perfluorocarbon emulsions for diverse applications.