2 results
Search Results
Now showing 1 - 2 of 2
- ItemHybrid surface patterns mimicking the design of the adhesive toe pad of tree frog(Washington D.C. : American Chemical Society, 2017) Xue, Longjian; Sanz, Belén; Luo, Aoyi; Turner, Kevin T.; Wang, Xin; Tan, Di; Zhang, Rui; Du, Hang; Steinhart, Martin; mijangos, Carmen; Guttmann, Markus; Kappl, Michael; del Campo, AránzazuBiological materials achieve directional reinforcement with oriented assemblies of anisotropic building blocks. One such example is the nanocomposite structure of keratinized epithelium on the toe pad of tree frogs, in which hexagonal arrays of (soft) epithelial cells are crossed by densely packed and oriented (hard) keratin nanofibrils. Here, a method is established to fabricate arrays of tree-frog-inspired composite micropatterns composed of polydimethylsiloxane (PDMS) micropillars embedded with polystyrene (PS) nanopillars. Adhesive and frictional studies of these synthetic materials reveal a benefit of the hierarchical and anisotropic design for both adhesion and friction, in particular, at high matrix−fiber interfacial strengths. The presence of PS nanopillars alters the stress distribution at the contact interface of micropillars and therefore enhances the adhesion and friction of the composite micropattern. The results suggest a design principle for bioinspired structural adhesives, especially for wet environments.
- Item3D Printed Tubular Scaffolds with Massively Tailorable Mechanical Behavior(Weinheim : Wiley-VCH, 2022) Pickering, Edmund; Paxton, Naomi C.; Bo, Arixin; O’Connell, Bridget; King, Mitchell; Woodruff, Maria A.Melt electrowriting (MEW) is a promising additive manufacturing technique for tissue scaffold biofabrication. Successful application of MEW scaffolds requires strictly controlled mechanical behavior. This requires scaffold geometry be optimized to match native tissue properties while simultaneously supporting cell attachment and proliferation. The objective of this work is to investigate how geometric properties can be exploited to massively tailor the mechanical behavior of tubular crosshatch scaffolds. An experimentally validated finite element (FE) model is developed and 441 scaffold geometries are investigated under tension, compression, bending, and radial loading. A range of pore areas (4–150 mm2) and pore angles (11°–134°) are investigated. It is found that scaffold mechanical behavior is massively tunable through the control of these simple geometric parameters. Across the ranges investigated, scaffold stiffness varies by a factor of 294× for tension, 204× for compression, 231× for bending, and 124× for radial loading. Further, it is discussed how these geometric parameters can be simultaneously tuned for different biomimetic material applications. This work provides critical insights into scaffold design to achieve biomimetic mechanical behavior and provides an important tool in the development of biomimetic tissue engineered constructs.