Electrically‐Controlled Multifunctional Double‐Emulsion Droplet Carrier Manipulation

Abstract Flexible manipulation of double‐emulsion droplet carriers is significant for lots of applications ranging from cell cultures to cargo delivery. However, the current techniques remain constrained by reliance on specialized platforms and unique functional materials, as well as the limitation to singular functionalities, thereby limiting their practical applicability. Herein, an innovative approach for multifunctional manipulations of double‐emulsion droplet carriers including transportation, rotation, and core release is introduced. Functional samples can be effortlessly encapsulated within the inner cores of droplet carriers, while the carrier shell is composed of a commonly used yet biologically harmless mixture of polydimethylsiloxane(PDMS) and silicone oil. In the designed microdevice, droplet carriers are initially transported from the channel entrances to the target region through the traveling‐wave dielectrophoresis effect, followed by the rotation under a rotating electric field for measuring the electric property of the droplet carrier. Ultimately, the shell‐thinning and final break is triggered by sufficient electric Maxwell stress at droplet interfaces, leading to the release of nanoparticles and anti‐cancer drugs. The modulation of droplet carriers can be flexibly adjusted by changing the voltage, frequency, and phase variation direction of electric signals. Therefore, this droplet manipulation method can be promising for many applications needing sample loading, delivery, and release.