Publications

This page lists most of our publications starting from 2014.

Total: ca. 150 Publications

Please refer to Google Scholar for a complete list.

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Multiple Light Control Mechanisms in ATP‐fueled Non‐Equilibrium DNA Systems

Read the full article here: Angew. Chem. Int. Ed. DOI:10.1002/anie.202003102 (2020). Fuel‐driven self‐assemblies are gaining ground for creating autonomous systems and materials, whose temporal behavior is preprogrammed by a reaction network. However, up to now there is a lack of simple external control mechanisms of the transient behavior, at best using remote and benign light control. Even more challenging is to use different wavelengths to modulate different components of the system, such as fuel or building blocks. Success would enable such systems to navigate along different trajectories in a wavelength‐dependent fashion. Herein, we introduce the first examples of light control in ATP‐f

Supracolloidal Self‐Assembly of Divalent Janus 3D DNA Origami via Programmable Multivalent Host/Gues

Read the full article here: Angew. Chem. Int. Ed. 59, 5515 (2020). We introduce divalent 3D DNA origami cuboids as truly monodisperse colloids and harness their ability for precision functionalization with defined patches and defined numbers of supramolecular binding motifs. We demonstrate that even adamantane/β‐cyclodextrin host/guest inclusion complexes of moderate association strength can induce efficient supracolloidal fibrillization at high dilution of the 3D DNA Origami as a result of cooperative multivalency. We show details on the assembly of Janus and non‐Janus 3D DNA origami into supracolloidal homo‐ and heterofibrils with respect to multivalency effects, electrostatic screening, a

Best Practice for Reporting Wet Mechanical Properties of Nanocellulose-based Materials

Read the full article here: Biomacromolecules DOI:10.1021/acs.biomac.0c00330 (2020). Nanocellulose-based materials and nanocomposites show extraordinary mechanical properties with high stiffness, strength, and toughness. Although the last decade has witnessed great progress in understanding the mechanical properties of these materials, a crucial challenge is to identify pathways to introduce high wet strength, which is a critical parameter for commercial applications. Because of the waterborne fabrication methods, nanocellulose-based materials are prone to swelling by both adsorption of moist air or liquid water. Unfortunately, there is currently no best practice on how to take the swelling

On the Permselectivity of Cation-Exchange Membranes Bearing an Ion Selective Coating

Read the full article here: J. Membr. Sci. 600, 117854 (2020). Monovalent ion selective membranes are permeable for monovalent ions while rejecting divalent ions to some extent. Different processes and applications like electrodialysis, microbial fuel cells, and flow batteries utilize such selective properties. Industrial membranes have a specific coating of equal charge to reject the bivalent counter ions. It has been suggested in the past that the current density regime at which such composite ion exchange membranes are operated can strongly influence their ion selectivity towards monovalent ions. Here, we now confirm this observation for a commercial CMS membrane as well as for a novel mi

Cellulose Nanofibril Hydrogel Promotes Hepatic Differentiation of Human Liver Organoids

Read the full article here: Adv. Healthcare Mater. 2020, 9, 1901658. To replicate functional liver tissue in vitro for drug testing or transplantation, 3D tissue engineering requires representative cell models as well as scaffolds that not only promote tissue production but also are applicable in a clinical setting. Recently, adult liver‐derived liver organoids are found to be of much interest due to their genetic stability, expansion potential, and ability to differentiate toward a hepatocyte‐like fate. The current standard for culturing these organoids is a basement membrane hydrogel like Matrigel (MG), which is derived from murine tumor material and apart from its variability and high cos

Structure, Mechanical Properties, and Dynamics of Polyethylenoxide/Nanoclay Nacre-Mimetic Nanocompos

Read the full article here: Macromolecules 2020, 53, 5, 1716-1725 Nacre-mimetic nanocomposites based on high fractions of synthetic high-aspect-ratio nanoclays in combination with polymers are continuously pushing boundaries for advanced material properties, such as high barrier against oxygen, extraordinary mechanical behavior, fire shielding, and glass-like transparency. Additionally, they provide interesting model systems to study polymers under nanoconfinement due to the well-defined layered nanocomposite arrangement. Although the general behavior in terms of forming such layered nanocomposite materials using evaporative self-assembly and controlling the nanoclay gallery spacing by the n

Pathway Complexity in Fuel-Driven DNA Nanostructures with Autonomous Reconfiguration of Multiple Dyn

Read the full article here: J. Am. Chem. Soc. 2020, 142, 2, 685 We introduce pathway complexity on a multicomponent systems level in chemically fueled transient DNA polymerization systems, achieving autonomous evolution over multiple structural dynamic steady states from monomers to dimers, oligomers of dimers, and randomized polymer structures before being ultimately degraded back to monomers once the fuel is consumed. The enabling key principle is to design monomer species having kinetically selected molecular recognition in the structure-forming step and which are reconfigured in an enzymatic reaction network. This nonequilibrium systems chemistry approach to pathway complexity provides n

Waterborne Methacrylate-Based Vitrimers

Read the full article here: ACS Macro Lett. 2020, 9, 1, 70 We demonstrate waterborne, unimolecularly dissolved vitrimer prepolymer systems that can be transferred into a vitrimer material using catalytic transesterification. The one-component prepolymer system can be processed via film casting and subsequent heat-induced cross-linking. A variation of the density of side chain hydroxy groups over ester and amide groups in the methacrylate/methacrylamide backbone, as well as of the Lewis acid catalyst loading, allow control of the extent of cross-linking and exchange rates. The increase of the amount of both catalyst and hydroxy groups leads to an acceleration of the relaxation times and a dec

Non‐Equilibrium, Light‐Adaptive, Steady‐State Reconfiguration of Mechanical Patterns in Bioinspired

Read the full article here: Adv. Funct. Mater. 1905309 (2019). Bioinspired nanocomposites have made great progress for the fabrication of mechanical high‐performance structural materials, but their properties have thus far been engineered with a focus on static behavior. This contrasts profoundly with the dynamic reconfiguration often observed in living tissues. Here, a first concept is introduced for steady‐state, light‐adaptive reconfiguration of mechanical patterns in bioinspired nanocomposites under dissipative out‐of‐equilibrium conditions. This is realized for green, waterborne cellulose nanofibril/polymer nanopapers by achieving a heterogeneous activation of a photothermal effect. To

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