We correlate network dynamics, supramolecular reversibility and the macroscopic surface scratch healing behavior for a series of ionomers based on an amorphous backbone with varying fractions of carboxylate pendant groups completely neutralized by Na⁺, Zn²⁺, or Co²⁺ as the counter ions.

Magnetic iron oxide, maghemite (Fe₂O₃) nanoparticles with covalent surface-bound CO-releasing molecules (CORMs) can be triggered to release CO through heating in an alternating magnetic field. In the proof-of-concept study the rate of CO-release from [RuCl(CO₃)(μ-DOPA)]@maghemite nanoparticles was doubled upon exposure to an external alternating magnetic field (31.7 kAm⁻¹, 247 kHz, 25 °C, 39.9 mTesla, DOPA = dioxyphenyl-alaninato).

Inhalation of (nano)particles may lead to pulmonary inflammation. However, the precise mechanisms of particle uptake and generation of inflammatory mediators by alveolar macrophages (AM) are still poorly understood. The aim of this study was to investigate the interactions between particles and AM and their associated pro-inflammatory effects in relation to particle size and physico-chemical properties.NR8383 rat lung AM were treated with ultrafine (uf), fine (f) TiO₂or fine crystalline silica (DQ12 quartz). Physico-chemical particle properties were investigated by transmission electron microscopy, elemental analysis and thermogravimetry. Aggregation and agglomeration tendency of the particles were determined in assay-specific suspensions by means of dynamic light scattering.All three particle types were rapidly taken up by AM. DQ12 and ufTiO₂, but not fTiO₂, caused increased extracellular reactive oxygen species (ROS), heme oxygenase 1 (HO-1) mRNA expression and tumor necrosis factor (TNF)-α release. Inducible nitric oxide synthase (iNOS) mRNA expression was increased most strongly by ufTiO₂, while DQ12 exclusively triggered interleukin (IL) 1β release. However, oscillations of intracellular calcium concentration and increased intracellular ROS were observed with all three samples. Uptake inhibition experiments with cytochalasin D, chlorpromazine and a Fcγ receptor II (FcγRII) antibody revealed that the endocytosis of fTiO₂by the macrophages involves actin-dependent phagocytosis and macropinocytosis as well as clathrin-coated pit formation, whereas the uptake of ufTiO₂was dominated by FcγIIR. The uptake of DQ12 was found to be significantly reduced by all three inhibitors. Our findings suggest that the contrasting AM responses to fTiO₂, ufTiO₂and DQ12 relate to differences in the involvement of specific uptake mechanisms.

In this review article, we provide an introduction to ferrogels, i.e. polymeric gels with embedded magnetic particles. Due to the interplay between magnetic and elastic properties of these materials, they are promising candidates for engineering and biomedical applications such as actuation and controlled drug release. Particular emphasis will be put on the polymer architecture of magnetic gels since it controls the degrees of freedom of the magnetic particles in the gel, and it is important for the particle-polymer coupling determining the mechanisms available for the gel deformation in magnetic fields. We report on the different polymer architectures that have been realized so far, and provide an overview of synthesis strategies and experimental techniques for the characterization of these materials. We further focus on theoretical and simulational studies carried out on magnetic gels, and highlight their contributions towards understanding the influence of the gels’ polymer architecture.

Significant advances in the field of responsive hydrogels have been achieved by the combination of soft, gel-based matrices with the unique functions of inorganic or biological nanostructures. Like in many biological tissues, the components of such hybrid materials often have converse, yet complementary properties. The possibility of forming self-assembled and supramolecular morphologies from organic polymers in combination with inorganic nanoparticles or biological motifs is of interest for gels with new response properties. A variety of complex gel structures with unique chemical, physical, and biological properties have been engineered or discovered at the nanoscale. In this review, we highlight recent accomplishments and trends in the field of hybrid polymer hydrogels with a focus on approaches towards soft, yet tough shape-changing and actuating materials. We conclude with an outline on future directions and challenges that have to be faced in the design and application of hybrid hydrogels.

Systematic structure-property investigations on the time-dependent mechanical properties of an ionomer model system with variation of the ionic fraction and the counter ion as obtained from SAXS, dynamic oscillatory rheology and tensile tests, deliver the prerequisites and tools for property adjustment and optimization of their self-healing efficiency.