am0c18221_si_002.mp4 (8.53 MB)
Download file3D-Printed Multi-Stimuli-Responsive Mobile Micromachines
media
posted on 30.12.2020, 18:37 authored by Yun-Woo Lee, Hakan Ceylan, Immihan Ceren Yasa, Ugur Kilic, Metin SittiMagnetically actuated
and controlled mobile micromachines have
the potential to be a key enabler for various wireless lab-on-a-chip
manipulations and minimally invasive targeted therapies. However,
their embodied, or physical, task execution capabilities that rely
on magnetic programming and control alone can curtail their projected
performance and functional diversity. Integration of stimuli-responsive
materials with mobile magnetic micromachines can enhance their design
toolbox, enabling independently controlled new functional capabilities
to be defined. To this end, here, we show three-dimensional (3D) printed
size-controllable hydrogel magnetic microscrews and microrollers that
respond to changes in magnetic fields, temperature, pH, and divalent
cations. We show two-way size-controllable microscrews that can reversibly
swell and shrink with temperature, pH, and divalent cations for multiple
cycles. We present the spatial adaptation of these microrollers for
penetration through narrow channels and their potential for controlled
occlusion of small capillaries (30 μm diameter). We further
demonstrate one-way size-controllable microscrews that can swell with
temperature up to 65% of their initial length. These hydrogel microscrews,
once swollen, however, can only be degraded enzymatically for removal.
Our results can inspire future applications of 3D- and 4D-printed
multifunctional mobile microrobots for precisely targeted obstructive
interventions (e.g., embolization) and lab- and organ-on-a-chip manipulations.