Creatures, such as Venus flytrap and hummingbirds, capable of rapid predation through snap-through transition, provide paradigms for the design of soft actuators and robots with fast actions. However, these artificial "snappers" usually need contact stimulations to trigger the flipping. Reported here is a constrained anisotropic poly(N-isopropylacrylamide) hydrogel showing fast snapping upon light stimulation.
View Article and Find Full Text PDFHydrogels are an ideal material to develop soft robots. However, it remains a grand challenge to develop miniaturized hydrogel robots with mechanical robustness, rapid actuation, and multi-gait motions. Reported here is a facile strategy to fabricate hydrogel-based soft robots by three-dimensional (3D) printing of responsive and nonresponsive tough gels for programmed morphing and locomotion upon stimulations.
View Article and Find Full Text PDFReported here is a multi-response anisotropic poly(N-isopropylacrylamide) hydrogel developed by using a rotating magnetic field to align magnetic double stacks (MDSs) that are fixed by polymerization. The magneto-orientation of MDSs originates from the unique structure with γ-Fe O nanoparticles sandwiched by two silicate nanosheets. The resultant gels not only exhibit anisotropic optical and mechanical properties but also show anisotropic responses to temperature and light.
View Article and Find Full Text PDFAnisotropic structures are ubiquitous in nature, affording fascinating morphing behaviors. Biomimetic morphing materials can be developed by spatially controlling the orientations of molecules or nanofillers that produce anisotropic responses and internal stresses under external stimuli. However, it remains a serious challenge to fabricate materials with sophisticated anisotropic architectures.
View Article and Find Full Text PDFGradient materials exist widely in natural living organisms, affording fascinating biological and mechanical properties. However, the synthetic gradient hydrogels are usually mechanically weak or only have relatively simple gradient structures. Here, we report on tough nanocomposite hydrogels with designable gradient network structure and mechanical properties by a facile post-photoregulation strategy.
View Article and Find Full Text PDFLiving organisms use musculatures with spatially distributed anisotropic structures to actuate deformations and locomotion with fascinating functions. Replicating such structural features in artificial materials is of great significance yet remains a big challenge. Here, a facile strategy is reported to fabricate hydrogels with elaborate ordered structures of nanosheets (NSs) oriented under a distributed electric field.
View Article and Find Full Text PDFACS Appl Mater Interfaces
November 2019
Shape memory hydrogels have drawn increasing attention in recent years. Practical applications require these hydrogels to have good mechanical properties as well as contactless stimulations to trigger the shape deformations. Here we report a stiff and tough shape memory hydrogel that can transform to various configurations sequentially by phototriggered site-specific deformations.
View Article and Find Full Text PDFBackground: Many studies have demonstrated that epidermal growth factor receptor (EGFR) mutation is associated with the response to therapy with single agent EGFR-tyrosine kinase inhibitors (EGFR-TKI) in non-small cell lung cancer (NSCLC) patients, but the extent of the effect is varied. We carried out a meta-analysis to assess the association between EGFR mutation and the efficacy of EGFR-TKI therapy and the independent predictor of EGFR mutation in order to identify who would be likely to benefit from this kind of therapy.
Methods: All literature relating to EGFR mutation and EGFR-TKI therapy was researched and carefully selected.