Production of microbubbles for use as echo contrast agents

Area of Science:

• Medical Imaging
• Biomedical Engineering
• Materials Science

Background:

• Microbubbles are effective ultrasound contrast agents due to superior sonographic resolution.
• Existing methods for microbubble production may lack precise size calibration.

Purpose of the Study:

• To describe a novel method for producing calibrated microbubbles for ultrasound contrast.
• To enable precise control over microbubble size for enhanced imaging.

Main Methods:

• Utilized a Plexiglas microbubbler apparatus with fine needle for gas injection.
• Employed differential absorption using tris(hydroxymethyl)aminomethane hydrochloride (THAM) to selectively absorb carbon dioxide.
• Calibrated microbubble size using the electric gating principle of the Coulter Counter.

Main Results:

• Produced microbubbles initially in the 40-100 micron size range, composed of nitrogen and carbon dioxide.
• Successfully reduced microbubble size through selective carbon dioxide absorption.
• Achieved calibrated microbubbles suitable for ultrasound contrast applications.

Conclusions:

• The described method allows for the production of calibrated microbubbles.
• This technique offers a pathway to improved ultrasound contrast agent development.
• Precise microbubble sizing is crucial for optimizing ultrasound imaging performance.