Dynamic satellite–parent liposome networks for quantitative microreactions

Abstract

The hierarchical assembly of liposomes into interconnected networks forms the basis for creating rudimentary artificial multicellular systems. Each vesicle performs specialized functions both temporally and spatially, replicating the complexity of living tissues. Controlling the size and number of liposomes in artificial multicellular systems and their dynamic interactions are necessary for quantitative bioprocesses but remain challenging. Here, we develop a satellite–parent liposome network—a central parent liposome surrounded by smaller satellite liposomes. This structure spontaneously forms during the dewetting transition of microfluidically prepared complex double emulsions. Intriguingly, the adhesion strength between the satellites and the parent liposome can be tuned using environmental stimuli. The varying numbers of satellite liposomes provide an excellent platform for studying quantitative microreactions. To illustrate, we first explore the differences in molecular affinity between parent and satellite liposomes to achieve directional molecular transfer against concentration gradients. Then, we mimic quantitative signal transfer by performing enzymatic reactions, supplying substrates from different numbers of satellites to the parent liposomes. After the reaction, the satellites can be separated from the parent liposome on demand upon osmotic stimuli. This work showcases an exceptional dynamic liposome network that will facilitate the mimicry of the complexity of multicellular systems in vitro.