Needleless Electrohydrodynamic Cojetting of Bicompartmental Particles and Fibers from an Extended Fluid Interface

Abstract

Back Cover: 3D ordered macroporous films can be fabricated using ordered arrays of the monodispersed droplets as templates of the macropores, which are self-assembled in the space between two parallel flat glass plates. In the case with two or more layers, the lattice structure of the macroporous films also changes due to the confinement effects. Further details can be found in the article by Y. Iwai, Y. Uchida,* H. Yabu, and N. Nishiyama on page 1600502. Front Cover: 2D and 3D light-triggered modulation of hydrogel stiffness is described. UV lithography and 3D two-photon direct laser writing technology afford to alter hydrogel crosslinking degree in two and three dimensions, exploiting a specific chemistry design. Spatially controlled changes in hydrogel mechanical properties induce a biological response: elongated cells and higher proliferation are evident on 2D stiff patterns compared to the less cross-linked soft regions. 3D ordered macroporous films with a pore diameter of more than 100 μm can be fabricated using ordered arrays of monodispersed droplets self-assembling in the space between two flat glass plates as templates. As the gap between the glass plates changes, the number of the layer and the lattice structure of the macro-porous films change due to the confinement effects. A novel needleless electrohydrodynamic cojetting technique allows for the preparation of particles and fibers with two distinct compartments. Application of a high electric field results in the spontaneous formation of several distinct Taylor cones along a fluid interface, resulting in the deposition of bicompartmental fibers and particles. Production rates of fibers are more than 30 times higher than needle-based cojetting methods. Nanoparticles made by polymerization-induced self-assembly can show reversible stimulus-triggered polymorphism ("shape-shifting") that differs from the phase behaviour known for unimeric smart polymers. This review explains the background of this promising behaviour and summarises the current state-of-the-art. A hydrogel material with tailorable 2D and 3D cross-linking degree by conventional UV lithography and 3D two-photon direct laser writing technology is presented. Mechanical properties (e.g., stiffness) can be modulated to induce different cell behaviors: elongated cells and higher proliferation are evident on 2D stiff patterns compared to the less cross-linked soft regions. Communications

Waterproof and Breathable Electrospun Nanofibrous Membranes

“…Fortunately, there has been much pioneering work that is potential for addressing the limitation. Multi‐jet electrospinning, bubble electrospinning, needleless electrospinning, and other modified electrospinning techniques have already been developed, effectively improving the production rates of electrospinning in one way . It is expected that these approaches can be applied to industrial preparation of W&B electrospun membranes.…”

Soft Matter Technology at KIT: Chemical Perspective from Nanoarchitectures to Microstructures

“…d) PPX-backbone modification by incorporation of nitrogen heteroatoms increases endothelial cell adhesion. [51] Copyright 2016, Wiley-VCH. e-1) Dual capillary needle system used for EHD co-jetting-the system can be extended up to seven side-by-side capillaries.…”

“…e) Electro-hydrodynamic (EHD) co-jetting process to create micro-to nanoparticles and microcylinders. [51] Copyright 2016, Wiley-VCH. e-2) The twisting motion of two threads actuated by two oppositely directed rotary axes leading to helical fibers.…”

“…Triggered by external stimuli, spherical-or cylindrical-shaped colloids respond by swelling, degrading, shape-/size-/curvature-shifting, moving, or rhythmic bending behavior, thus, being candidates for controlled drug release, synthetic sensors, bioactuators, or even miniaturized biorobots. [51] Moreover, helical bicompartmental fibers are manufacturable by in situ twisting of the two threads into opposite directions during co-electrospinning with a collector system containing two rotary axes (Figure 3e-2). [47,48] EHD was optimized for anisotropic particles and microcylinders by Lahann et al (Figure 3e).…”

“…[50] An alignment of the jetted fibers can be achieved by implying a secondary ring electrode. [51] EHD particles and cylinders compelled to a specific form or motion by environmental triggers are presented in the following (Figure 3f). [52] Microtubular particles with a defined thickness from 10 to 200 µm are featured by cryosectioning of the jetted fibers.…”