2014, Chattopadhyay, Subrata, Heine, Elisabeth, Keul, Helmut, Moeller, Martin

In this work, we report the antimicrobial efficacy of azetidinium functionalized polytetrahydrofurans in solution and their application in the preparation of non leaching, antimicrobial surfaces. The excellent antimicrobial efficacy of these water soluble polymers both in solution and on surfaces (>99.99%–100% bacterial growth inhibition) makes them excellent candidates for solving the hygiene related problems in the medical and hospital environment.

2017, Das, Paramita, Thomas, Helga, Moeller, Martin, Walther, Andreas

A 3-dimensional Block Copolymer Micellar nanoLithography (BCML) process was used to prepare AuxPt1−x alloy nanoparticles (NPs) monodisperse in size and composition, strongly anchored onto SiO2-particles (0.2 wt.% AuxPt1−x/SiO2). The particles possess a face-centered cubic (fcc) crystal structure and their size could be varied from 3–12 nm. We demonstrate the uniformity of the Au/Pt composition by analyzing individual NPs by energy-dispersive X-ray spectroscopy. The strongly bound AuxPt1−x NPs catalyzed the oxidation of CO with high activity. Thermal ageing experiments in pure CO2 as well as in ambient atmosphere demonstrated stability of the size distribution for times as long as 22 h.

2020, Nishiguchi, Akihiro, Shima, Fumiaki, Singh, Smriti, Akashi, Mitsuru, Moeller, Martin

Targeted delivery of antigens to immune cells using micro/nanocarriers may serve as a therapeutic application for vaccination. However, synthetic carriers have potential drawbacks including cytotoxicity, low encapsulation efficiency of antigen, and lack of a morphological design, which limit the translation of the delivery system to clinical use. Here, we report a carrier-free and three-dimensional (3D)-shape-designed antigen nanoparticle by multiphoton lithography-based 3D-printing. This simple, versatile 3D-printing approach provides freedom for the precise design of particle shapes with a nanoscale resolution. Importantly, shape-designed antigen nanoparticles with distinct aspect ratios show shape-dependent immune responses. The 3D-printing approach for the rational design of nanomaterials with increasing safety, complexity, and efficacy offers an emerging platform to develop vaccine delivery systems and mechanistic understanding.

2018, Koens, Lyndon, Zhang, Hang, Moeller, Martin, Mourran, Ahmed, Lauga, Eric

Many microorganisms and artificial microswimmers use helical appendages in order to generate locomotion. Though often rotated so as to produce thrust, some species of bacteria such Spiroplasma, Rhodobacter sphaeroides and Spirochetes induce movement by deforming a helical-shaped body. Recently, artificial devices have been created which also generate motion by deforming their helical body in a non-reciprocal way (A. Mourran et al. Adv. Mater. 29, 1604825, 2017). Inspired by these systems, we investigate the transport of a deforming helix within a viscous fluid. Specifically, we consider a swimmer that maintains a helical centreline and a single handedness while changing its helix radius, pitch and wavelength uniformly across the body. We first discuss how a deforming helix can create a non-reciprocal translational and rotational swimming stroke and identify its principle direction of motion. We then determine the leading-order physics for helices with small helix radius before considering the general behaviour for different configuration parameters and how these swimmers can be optimised. Finally, we explore how the presence of walls, gravity, and defects in the centreline allow the helical device to break symmetries, increase its speed, and generate transport in directions not available to helices in bulk fluids.