Microbubbles with a Self-Assembled Poloxamer Shell and a Fluorocarbon Inner Gas

Area of Science:

• Food Science
• Materials Science
• Biophysics

Background:

• Microbubbles have diverse applications in food science and medicine.
• Understanding shell properties is key to controlling microbubble stability and resonance.
• Poloxamer 188 (Pluronic F-68) is commonly used as a dispersing agent, but its role as a shell component is unexplored.

Purpose of the Study:

• Investigate Poloxamer 188 as a microbubble shell component.
• Determine the effect of Poloxamer 188 and perfluorohexane (F-hexane) on microbubble stability and acoustic properties.
• Explore the adsorption kinetics and interfacial properties of Poloxamer 188.

Main Methods:

• Bubble profile tensiometry to analyze adsorption kinetics and interfacial tension.
• Microbubble preparation using Poloxamer 188 with and without F-hexane.
• Laser Doppler vibratometry for single-bubble acoustic response measurements.

Main Results:

• F-hexane significantly accelerated Poloxamer 188 adsorption and reduced interfacial tension.
• Stable microbubbles were formed using Poloxamer 188 and F-hexane, exhibiting limited volume changes.
• Poloxamer 188-coated bubbles showed reduced resonance radius and lower vibrational displacement amplitude, indicating decreased elasticity, especially with F-hexane.

Conclusions:

• Poloxamer 188 can form stable microbubble shells, particularly when F-hexane is present.
• The presence of F-hexane enhances microbubble stability and modifies their acoustic behavior.
• These findings offer insights into tailoring microbubble properties for specific ultrasound applications.