Remote Loading of Gas Bubbles into Polylactic Acid Microcapsules Creates Acoustically Active Janus Particles

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Nanotechnology

Background:

• Polymeric microcapsules (MCs) are versatile biocompatible agents.
• Applications include drug delivery and in vivo imaging.

Purpose of the Study:

• To develop a method for remotely loading air into polylactic acid (PLA)-based MCs.
• To investigate the formation of gas-filled Janus particles.

Main Methods:

• Suspending PLA-based MCs with aqueous cores in glycerol and propylene glycol solutions.
• Utilizing changes in gas solubility to induce bubble nucleation via an "Ouzo-like" effect.
• Observing the localization of residual content to create Janus particles.

Main Results:

• Successfully achieved remote air loading into PLA-based MCs.
• Demonstrated the formation of gas-filled Janus particles with localized internal content.
• The "Ouzo-like" effect drives bubble nucleation and content redistribution.

Conclusions:

• A novel method for creating Janus particles from polymeric microcapsules has been established.
• This technique offers a new platform for advanced drug delivery and imaging agents.
• The controlled formation of Janus particles has significant implications for biomaterials engineering.