The 3D-printed device can be programmed to carry out multistep, complex chemical reactions on demand and can be reconfigured to efficiently and precisely combine molecules to form very specific products.

The multitasking device can also be programmed to function like an artificial circulatory system that separates molecules flowing through the channel and automatically removes unwanted byproducts while it continues to print a sequence of bridges to specific catalysts, and carry out the steps of chemical synthesis.

Abstract
Systems comprised of immiscible liquids held in non-equilibrium shapes by the interfacial assembly and jamming of nanoparticle−polymer surfactants have significant potential to advance catalysis, chemical separations, energy storage and conversion. Spatially directing functionality within them and coupling processes in both phases remains a challenge. Here, we exploit nanoclay−polymer surfactant assemblies at an oil−water interface to produce a semi-permeable membrane between the liquids, and from them all-liquid fluidic devices with bespoke properties. Flow channels are fabricated using micropatterned 2D substrates and liquid-in-liquid 3D printing.