Rotational 3D printing of active-passive filaments and lattices with programmable shape morphing

Open MIND · 2026-03-05

Natural filaments, such as proteins, plant tendrils, octopus tentacles, and elephant trunks, can transform into arbitrary three-dimensional shapes that carry out vital functions. Their shape-morphing behavior arises from intricate patterning of active and passive regions, which are difficult to replicate in synthetic matter. Here, we introduce a filament-centric strategy for programmable shape morphing in which intrinsic curvature and twist are directly encoded within multimaterial elastomeric filaments during fabrication. By harnessing rotational multimaterial 3D printing (RM-3DP), we directly prescribe the filament's natural curvature--twist field $\mathbf{k}(s)$ through controlled material distribution and helical liquid crystal mesogen alignment. When heated above their nematic-to-isotropic transition temperature ($T_\mathrm{NI}$), the helically aligned LCE regions contract along their local director field, while passive regions remain essentially unchanged. This approach enables independent control of bending and torsion at every cross-section along the filament centerline: the principal natural curvatures of the filament along two orthogonal axes as well as the local twist. Next, we printed architected lattices composed of unit cells formed by sinusoidal filaments that either reversibly contract, expand, or exhibit out-of-plane deformations. Discrete elastic rod simulations of Janus filaments with different natural curvatures and twist, which are interconnected within the printed lattices, allow accurate prediction of their observed shape-morphing behavior. By integrating active-passive elastomers, additive manufacturing, and computational modeling, we have created shape-morphing matter with complex programmable responses for applications that rely on adaptive, robotic, or deployable architectures.

Embedding Perfusable Microchannel Networks in Photoclickable Bioresins via High‐Resolution Digital Light Processing

Advanced Materials Technologies · 2026-02-12

ABSTRACT Light‐mediated 3D bioprinting methods hold great promise for the generation of biomimetic microvasculature networks for applications ranging from organ‐on‐chip models to vascularized tissue constructs. While printing microvascular channels (≤100 µm in diameter) within large hydrogel volumes (≥1 cm 3 ) is theoretically feasible, progress remains limited by the lack of suitable cytocompatible photoresins. Here, we report the development of an optimized photoresin based on fish gelatin and photoclick crosslinking chemistry for bioprinting perfusable, embedded microvascular networks via high‐resolution digital light processing (DLP). Specifically, our hydrogel matrix leverages the fast kinetics and negligible dark curing of thiol‐norbornene crosslinking as well as the low viscosity and thermal stability of fish gelatin. Using pulsed illumination and a biocompatible radical scavenger (DMPO), we further minimize radical diffusion‐induced blurring, enabling extended printing (>5 h). Finally, printing failures are reduced through the incorporation of a cytocompatible surfactant (Poloxamer‐188). Together, these advances open new avenues for printing perfusable biomimetic microvascular networks embedded in hydrogel matrices.

Rotational 3D printing of active–passive filaments and lattices with programmable shape morphing

Proceedings of the National Academy of Sciences · 2026-04-22

Natural filaments, such as proteins, plant tendrils, octopus tentacles, and elephant trunks, can transform into arbitrary three-dimensional shapes that carry out vital functions. Their shape-morphing behavior arises from intricate patterning of active and passive regions, which are difficult to replicate in synthetic matter. Here, we introduce a filament-centric strategy for programmable shape morphing in which intrinsic curvature and twist are directly encoded within multimaterial elastomeric filaments during fabrication. By harnessing rotational multimaterial 3D printing, we directly prescribe the filament’s natural curvature–twist field κ(s) through controlled material distribution and helical liquid crystal mesogen alignment. When heated above their nematic-to-isotropic transition temperature ( T NI ), the helically aligned liquid crystal elastomer regions contract along their local director field, while passive regions remain essentially unchanged. This approach enables independent control of bending and torsion at every cross-section along the filament centerline: the principal natural curvatures of the filament along two orthogonal axes as well as the local twist. Next, we printed architected lattices composed of unit cells formed by sinusoidal filaments that either reversibly contract, expand, or exhibit out-of-plane deformations. Discrete elastic rod simulations of Janus filaments with different natural curvatures and twist, which are interconnected within the printed lattices, allow accurate prediction of their observed shape-morphing behavior. By integrating active–passive elastomers, additive manufacturing, and computational modeling, we have created shape-morphing matter with complex programmable responses for applications that rely on adaptive, robotic, or deployable architectures.

Rotational 3D printing of active-passive filaments and lattices with programmable shape morphing

ArXiv.org · 2026-03-05

Natural filaments, such as proteins, plant tendrils, octopus tentacles, and elephant trunks, can transform into arbitrary three-dimensional shapes that carry out vital functions. Their shape-morphing behavior arises from intricate patterning of active and passive regions, which are difficult to replicate in synthetic matter. Here, we introduce a filament-centric strategy for programmable shape morphing in which intrinsic curvature and twist are directly encoded within multimaterial elastomeric filaments during fabrication. By harnessing rotational multimaterial 3D printing (RM-3DP), we directly prescribe the filament's natural curvature--twist field $\mathbf{k}(s)$ through controlled material distribution and helical liquid crystal mesogen alignment. When heated above their nematic-to-isotropic transition temperature ($T_\mathrm{NI}$), the helically aligned LCE regions contract along their local director field, while passive regions remain essentially unchanged. This approach enables independent control of bending and torsion at every cross-section along the filament centerline: the principal natural curvatures of the filament along two orthogonal axes as well as the local twist. Next, we printed architected lattices composed of unit cells formed by sinusoidal filaments that either reversibly contract, expand, or exhibit out-of-plane deformations. Discrete elastic rod simulations of Janus filaments with different natural curvatures and twist, which are interconnected within the printed lattices, allow accurate prediction of their observed shape-morphing behavior. By integrating active-passive elastomers, additive manufacturing, and computational modeling, we have created shape-morphing matter with complex programmable responses for applications that rely on adaptive, robotic, or deployable architectures.

Rational Design and Synthesis of Zwitterionic Polysiloxanes with Extreme Dielectric Permittivity

ChemRxiv · 2026-02-24

The design and synthesis of high permittivity polymers face a key challenge; namely, strong polarization requires concentrated dipoles that give rise to high thermal transition temperatures. The inverse relationship between permittivity and mobility limits the dielectric constant of all dipolar materials. Consequently, for pure polymers, the largest known dielectric constants are roughly 100 for vinylidene fluoride copolymers at the Curie temperature and 35 for room-temperature polymer melts. Here, we report the rational design and synthesis of a zwitterionic polysiloxane with a static dielectric constant of 420 at room temperature, the largest value achieved to date. This specific polysiloxane contains pendent zwitterionic dipoles with long, flexible spacers that simultaneously amplify dipole moment and dilute strong coulombic interactions, yielding a glass transition temperature Tg of-14 °C. This novel high-κ dielectric polymer overcomes the permittivity-mobility limitation thereby challenging the existing paradigm for dipolar polymer dielectrics.

Zwitterionic Polysiloxanes with Extreme Dielectric Permittivity

ChemRxiv · 2026-05-03

The design and synthesis of high permittivity polymers face a key challenge; namely, strong polarization requires concentrated dipoles that give rise to high thermal transition temperatures. The inverse relationship between permittivity and mobility limits the dielectric constant of all dipolar materials. Consequently, for pure polymers, the largest known dielectric constants are roughly 100 for vinylidene fluoride copolymers at the Curie temperature and 35 for room-temperature polymer melts. Here, we report the rational design and synthesis of a zwitterionic polysiloxane with a static dielectric constant of 420 at room temperature, the largest value achieved to date. This specific polysiloxane contains pendent zwitterionic dipoles with long, flexible spacers that simultaneously amplify dipole moment and dilute strong coulombic interactions, yielding a glass transition temperature Tg of-14 °C. This novel high-κ dielectric polymer overcomes the permittivity-mobility limitation thereby challenging the existing paradigm for dipolar polymer dielectrics.

Embedding Perfusable Microchannel Networks in Photoclickable Bioresins via High-Resolution Digital Light Processing

bioRxiv (Cold Spring Harbor Laboratory) · 2025-10-30 · 1 citations

Abstract Light-mediated 3D bioprinting methods hold great promise for the generation of biomimetic microvasculature networks for applications ranging from organ-on-chip models to vascularized tissue constructs. While printing microvascular channels (≤100 µm in diameter) within large hydrogel volumes (≥1 cm³) is theoretically feasible, progress remains limited by the lack of suitable biocompatible photoresins. Here, we report the development of an optimized photoresin based on fish gelatin and photoclick crosslinking chemistry for bioprinting perfusable, embedded microvascular networks via high-resolution digital light processing (DLP). Specifically, our biocompatible matrix leverages the fast kinetics and negligible dark curing of thiol-norbornene crosslinking as well as the low viscosity and thermal stability of fish gelatin. Using pulsed illumination and a biocompatible radical scavenger (DMPO), we further minimize radical diffusion-induced blurring, enabling extended printing (>5 h). Finally, printing failures are reduced through the incorporation of a biocompatible surfactant (Poloxamer-188). Together, these advances open new avenues for printing perfusable biomimetic microvascular networks embedded in biocompatible hydrogel matrices.

Ca²⁺signaling dynamics in maturing ureteric bud (UB) and collecting duct (CD)-derived organoid tubules

Physiology · 2025-05-01

Ca 2+ signaling in metanephric mesenchymal (MM) cells contributes to key pattern forming events including branching morphogenesis in the embryonic rat kidney (Fontana et al., FASEB J, 2019). We previously reported that basolateral exposure of tubular structures isolated from MM-derived kidney organoids to the PIEZO1 channel agonist Yoda1 elicited a maturation stage-dependent elevation of intracellular Ca 2+ concentration, [Ca 2+ ] i (Carrisoza-Gaytán et al., AJP Cell Physiol, 2023). The aim of our current study is to explore whether tubular cells in human iPSC-derived UB and CD organoids exhibit similar developmental increases in PIEZO1 function.To investigate this, tubular structures from UB and CD organoids cultured for 34-35 or 61-65 d (4 tubules/group; n=38-40 cells/group) are loaded with the Ca 2+ -sensitive fluorophore Fura2-AM to measure [Ca 2+ ] i before and after basolateral exposure to Yoda1 (5 µM). Baseline [Ca 2+ ] i was 108.5±3.6 nM across all tubular cells studied, with no differences detected between UBs and CDs or days in culture. Subsequent exposure to Yoda1 induced an increase in [Ca 2+ ] i and appearance of Ca 2+ oscillations. The Yoda1-induced [Ca 2+ ] i signals of individually identified cells are then subject to spectral analysis using the multitaper method along with a harmonic F-test to identify predominant frequencies in the signal. We found that with advancing days in culture from 34-35 to 61-65 d: (i) Yoda1 induced an increase in [Ca 2+ ] i in UBs from 45.3±18.5 to 275.6±43.7 nM (p≤0.001) and in CDs from 61.7±16.1 to 254.3±56.2 nM (p≤0.001), (ii) the proportion of cells exhibiting Ca 2+ oscillations increased in UBs from 70 to 83% and in CDs from 75 to 84%, and (iii) the predominant oscillatory frequency fell by 50% in UBs and 30% in CDs from 15 mHz. These observations suggest that kidney organoids undergo a developmental increase in PIEZO1 abundance/activity and maturation of Ca 2+ signal transduction pathways, especially those involved in Ca 2+ oscillatory activity. Decoding Ca 2+ oscillations may unveil molecular mechanisms underlying maturation/differentiation. This work was supported by the NIH Re(Building) a Kidney Consortium (NIH UC2DK126023) and the Welcome LEAP Human Organs, Physiology and Engineering (HOPE) program. This abstract was presented at the American Physiology Summit 2025 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.

Print‐and‐Plate Architected Electrodes for Electrochemical Transformations Under Flow

Advanced Functional Materials · 2025-03-10

Abstract Flow cell electrodes are typically composed of porous carbon materials, such as papers, felts, and cloths. However, their random architecture hinders the fundamental characterization of electrode structure‐performance relationships during in situ operation of porous electrochemical flow systems. This work describes a “print‐and‐plate” method that combines direct ink writing of micro‐periodic lattices with a two‐step metal plating process that converts them into highly conductive (sheet resistance 40 mΩ sq −1 ) electrodes. Their operando performance is assessed in an anthraquinone disulfonic acid half‐cell using widefield electrochemical fluorescence microscopy, where output current and fluorescence intensity are in excellent agreement. The pressure drop associated with flow through three electrode designs is determined via simulations from which the most efficient design is identified and manufactured via print‐and‐plate. Confocal fluorescence microscopy is then used to create a 3D map of the state of charge (SOC) inside this print‐and‐plate electrode. The experimental state of the charge map is in good agreement with computational predictions. The rapid design, simulation, and fabrication of print‐and‐plate electrodes enable fundamental investigations of how architected porosity affects electrochemical performance under flow.

Controlled Frontal Polymerization and Direct Writing of Cyclooctadiene-based Inks

Zenodo (CERN European Organization for Nuclear Research) · 2025-01-01