Pickering Bubbles as Dual-Modality Ultrasound and Photoacoustic Contrast Agents

Area of Science:

• Materials Science
• Biomedical Engineering
• Nanotechnology

Background:

• Microbubbles (MBs) stabilized by particle surfactants offer superior thermodynamic stability over small-molecule stabilized MBs.
• Particles stabilizing MBs can impart photoacoustic (PA) properties, enabling dual-modality ultrasound (US) and PA imaging.
• Current dual-modality agents often require small-molecule or polymer additives, complicating formulation and potentially limiting PA agent loading.

Purpose of the Study:

• To develop a dual-modality ultrasound and photoacoustic contrast agent using a novel surfactant.
• To investigate the use of partially reduced and functionalized graphene oxide as the sole surfactant for stabilizing perfluorocarbon gas bubbles.
• To evaluate the contrast enhancement and stability of the developed agent in both US and PA imaging modes.

Main Methods:

• Preparation of perfluorocarbon gas bubbles stabilized solely by partially reduced and functionalized graphene oxide nanoparticles.
• Characterization of the microbubble shell properties, including thickness and stability.
• Evaluation of the dual-modality contrast performance in both ultrasound and photoacoustic imaging.

Main Results:

• Successfully stabilized perfluorocarbon gas bubbles using graphene oxide as the sole surfactant.
• Achieved high contrast in both ultrasound and photoacoustic imaging modalities.
• Demonstrated increased loading of the PA agent and enhanced MB shell thickness without destabilization compared to traditional systems.
• Eliminated the need for small-molecule or polymer additives in the formulation.

Conclusions:

• Partially reduced and functionalized graphene oxide is an effective sole surfactant for creating stable, dual-modality ultrasound and photoacoustic microbubbles.
• This approach offers a simplified formulation with improved PA agent loading and MB shell integrity.
• The developed agent shows significant promise for advanced biomedical imaging applications.