Responsive soft materials capable of exhibiting various three-dimensional (3D) shapes under the same stimulus are desirable for promising applications including adaptive and reconfigurable soft robots. Here, we report a laser rewritable magnetic composite film, whose responsive shape-morphing behaviors induced by a magnetic field can be digitally and repeatedly reprogrammed by a facile method of direct laser writing. The composite film is made from an elastomer and magnetic particles encapsulated by a phase change polymer. Once the phase change polymer is temporarily melted by transient laser heating, the orientation of the magnetic particles can be re-aligned upon change of a programming magnetic field. By the digital laser writing on selective areas, magnetic anisotropies can be encoded in the composite film and then reprogrammed by repeating the same procedure, thus leading to multimodal 3D shaping under the same actuation magnetic field. Furthermore, we demonstrated their functional applications in assembling multistate 3D structures driven by the magnetic force-induced buckling, fabricating multistate electrical switches for electronics, and constructing reconfigurable magnetic soft robots with locomotion modes of peristalsis, crawling, and rolling.

Ever-increasing demand on novel polymers with superior properties requires deeper understanding and exploration of the chemical space. Recently, data-driven approaches to explore the chemical space for polymer design are emerging....

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The excitation-contraction dynamics in cardiac tissue are the most important physiological parameters for assessing developmental state. We demonstrate integrated nanoelectronic sensors capable of simultaneously probing electrical and mechanical cellular responses. The sensor is configured from a three-dimensional nanotransistor with its conduction channel protruding out of the plane. The structure promotes not only a tight seal with the cell for detecting action potential via field effect but also a close mechanical coupling for detecting cellular force via piezoresistive effect. Arrays of nanotransistors are integrated to realize label-free, submillisecond, and scalable interrogation of correlated cell dynamics, showing advantages in tracking and differentiating cell states in drug studies. The sensor can further decode vector information in cellular motion beyond typical scalar information acquired at the tissue level, hence offering an improved tool for cell mechanics studies. The sensor enables not only improved bioelectronic detections but also reduced invasiveness through the two-in-one converging integration.

Three-dimensional (3D) morphing structures with multistable shapes that can be quantitatively and reversibly altered are highly desired in many potential applications ranging from soft robots to wearable electronics. In this study, we present a 4D printing method for fabricating multistable shape-morphing structures that can be quantitatively controlled by the applied strains. The structures are printed by a two-nozzle 3D printer that can spatially distribute phase change wax microparticles (MPs) in the elastomer matrix. The wax MPs can retain the residual strain after the prestrained elastomer composite is relaxed because of the solid−liquid phase change. Thanks to high design freedom of the 3D printing, spatial distribution of the wax MPs can be programmed, leading to an anisotropic stress field in the elastomer composite. This causes the out-of-plane deformations such as curling, folding, and buckling. These deformations are multistable and can be reprogrammed because of the reversible phase change of the wax MPs. What's more, characteristics of deformations such as curvatures and folding angles are linearly dependent on the applied strains, suggesting that these deformations are quantitatively controllable. Finally, the applications of the strained-tailored multistable shape morphing 3D structures in the assembly of 3D electronics and adaptive wearable sensors were demonstrated.