Many natural materials possess built-in structural variation, endowing them with superior performance. However, it is challenging to realize programmable structural variation in self-assembled synthetic materials since self-assembly processes usually generate uniform and ordered structures. Here, we report the formation of asymmetric microribbons composed of directionally self-assembled two-dimensional nanoflakes in a polymeric matrix during three-dimensional direct-ink printing. The printed ribbons with embedded structural variations show site-specific variance in their mechanical properties. Remarkably, the ribbons can spontaneously transform into ultrastretchable springs with controllable helical architecture upon stimulation. Such springs also exhibit superior nanoscale transport behavior as nanofluidic ionic conductors under even ultralarge tensile strains (>1,000%). Furthermore, to show possible real-world uses of such materials, we demonstrate in vivo neural recording and stimulation using such springs in a bullfrog animal model. Thus, such springs can be used as neural electrodes compatible with soft and dynamic biological tissues.
Download full-text PDF |
Source |
---|---|
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC7334571 | PMC |
http://dx.doi.org/10.1073/pnas.2003079117 | DOI Listing |
Adv Mater
August 2024
Department of Electrical Engineering, Stanford University, Stanford, CA, 94305, USA.
Phonon polaritons, the hybrid quasiparticles resulting from the coupling of photons and lattice vibrations, have gained significant attention in the field of layered van der Waals heterostructures. Particular interest has been paid to hetero-bicrystals composed of molybdenum oxide (MoO) and hexagonal boron nitride (hBN), which feature polariton dispersion tailorable via avoided polariton mode crossings. In this work, the polariton eigenmodes in MoO-hBN hetero-bicrystals self-assembled on ultrasmooth gold are systematically studied using synchrotron infrared nanospectroscopy.
View Article and Find Full Text PDFWe investigate the possibility of frequency conversion in time-varying metasurfaces, composed of graphene microribbon arrays (GMRAs) with time-periodic modulation of their conductivity. We present a quasi-static model for the interaction of light with a temporally modulated metasurface, as well as an accurate analytical treatment of the problem of time-varying GMRAs. Results coming from numerical simulations are also available.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
June 2020
Key Laboratory of Organic Optoelectronics and Molecular Engineering of the Ministry of Education, Department of Chemistry, Tsinghua University, 100084 Beijing, People's Republic of China;
Many natural materials possess built-in structural variation, endowing them with superior performance. However, it is challenging to realize programmable structural variation in self-assembled synthetic materials since self-assembly processes usually generate uniform and ordered structures. Here, we report the formation of asymmetric microribbons composed of directionally self-assembled two-dimensional nanoflakes in a polymeric matrix during three-dimensional direct-ink printing.
View Article and Find Full Text PDFActa Biomater
January 2020
Department of Bioengineering, Stanford University Schools of Engineering and Medicine, 300 Pasteur Drive, Edwards R114, Stanford, CA 94305, USA; Department of Orthopaedic Surgery, Stanford University School of Medicine, 300 Pasteur Dr., Edwards R105, Stanford, CA, 94305, USA. Electronic address:
Regenerating cartilage with biomimetic zonal organization, which is critical for tissue function, remains a great challenge. The objective of this study was to evaluate the potential of spatially-patterned, multi-compositional, macroporous, extracellular matrix-based microribbon (µRB) µRB scaffolds to regenerate cartilage with biochemical, mechanical, and morphological zonal organization by mesenchymal stem cells (MSCs) compared to conventional multi-layer nanoporous hydrogels. MSCs were seeded in either trilayer microribbon (µRB) or hydrogel (HG) scaffolds that were composed of layered biomaterial compositions that had been chosen for their ability to differentiate MSCs into chondrocytes with zonal properties.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
June 2018
Chemistry Department, University of California, Riverside, 501 Big Spring Road, Riverside, CA, 92521, USA.
A surfactant-assisted seeded-growth method is used to form single-crystal platelets composed of 9-methylanthracene with two different internal molecular orientations. The more stable form exhibits a photoinduced twisting, as observed previously for 9-methylanthracene microribbons grown by the floating drop method. However, the newly discovered elongated hexagonal platelets undergo a photoinduced rolling-up and unrolling.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!