Light-Triggered Inflation of Microdroplets

TL;DR

This paper introduces microdroplets that can inflate and burst when triggered by light, enabling controlled release of contents and inspiring new autonomous systems.

Contribution

The novelty lies in creating solid-in-oil composite microdroplets that can inflate and burst using uniform energy input.

Findings

Altering the energy input allows tuning of droplet inflation and burst timing.

Inflated droplets release inner contents, attracting colloidal particles temporarily.

The system can perform multiple inflation–burst cycles.

Abstract

Driven systems composed
largely of droplets and fuel
make up a
significant portion of microbiological function. At the micrometer
scale, fully synthetic systems that perform an array of tasks within
a uniform bulk are much more rare. In this work, we introduce an innovative
design for solid-in-oil composite microdroplets. These microdroplets
are engineered to nucleate an internal phase, undergo inflation, and
eventually burst, all powered by a steady and uniform energy input.
We show that by altering the background input, volumetric change and
burst time can be tuned. When the inflated droplets release the inner
contents, colloidal particles are shown to transiently attract to
the release point. Lastly, we show that the system has the ability
to perform multiple inflation–burst cycles. We anticipate that
our conceptual design of internally powered microdroplets will catalyze
further research into autonomous systems capable of intricate communication
as well as inspire the development of advanced, responsive materials.

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