Long-Lived Antibubbles: Stable Antibubbles through Pickering Stabilization

Antibubbles, which are liquid droplets surrounded by a thin shell of gas in a liquid phase, have several promising applications, among which is encapsulation. A major hurdle toward these applications has hitherto been the inherent instability of antibubbles, leading to lifetimes of at most minutes. Here we show the production of antibubbles with a lifetime of at least tens of hours, with their stability stemming from the adsorption of colloidal particles at gas-water interfaces. Antibubbles were produced by coating aqueous droplets with hydrophobic colloidal particles, gelling the droplets, and then dropping them into an aqueous colloidal suspension. This resulted in the formation of antibubbles with a long lifetime, also after the melting of the gel.