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Nickel magnetic nanowires (NWs) have attracted significant attention due to their unique properties, which are useful for basic studies and technological applications, for example in biomedicine. Their structure and magnetic properties were systematically studied in the recent years. In this work, Ni NWs with high aspect ratios (length/diameter ~250) were fabricated by electrodeposition into commercial anodic aluminum oxide templates. The templates were then etched and the NWs were suspended in water, where their hydrodynamic size was evaluated by dynamic light scattering. The magnetic response of these NWs as a function of an external magnetic field indicates a dominant shape anisotropy with propagation of the vortex domain wall as the main magnetization reversal process. The suspension of Ni NWs was used in the synthesis of two types of polyacrylamide ferrogels (FGs) by free radical polymerization, with weight fractions of Ni NWs in FGs of 0.036% and 0.169%. The FGs were reasonably homogeneous. The magnetic response of these FGs (hysteresis loops) indicated that the NWs are randomly oriented inside the FG, and their magnetic response remains stable after embedding. © 2019 by the authors.

The design of compartmentalized carriers for advanced drug delivery systems or artificial cells and organelles is of interest for biomedical applications. Herein, a polymer carrier microreactor that contains two different classes of subcompartments, multilayered polymer capsules and liposomes, is presented. 50 nm-diameter liposomes and 300 nm-diameter polymer capsules are encapsulated into a larger polymer carrier capsule, demonstrating control over the spatial positioning of the subcompartments, which are either 'membrane-associated' or 'free-floating' in the aqueous interior. Selective and spatially dependent degradation of the 300 nm-diameter subcompartments (without destroying the structural integrity of the enzyme-loaded liposomes) is also shown, by performing an encapsulated enzymatic reaction using the liposomal subcompartments. These findings cover several important aspects toward the development of engineered compartmentalized carrier vessels for the creation of artificial cell mimics or advanced therapeutic delivery systems.

Liposomes are widely used, from biosensing to drug delivery. Their coating with polymers for stability and functionalization purposes further broadens their set of relevant properties. Poly(dopamine) (PDA), a eumelanin-like material deposited via the "self"-oxidative polymerization of dopamine at mildly basic pH, has attracted considerable interest in the past few years due to its simplicity, flexibility yet fascinating properties. Herein, we characterize the coating of different types of liposomes with PDA depending on the presence of oleoyldopamine in the lipid bilayer and the dopamine hydrochloride concentration. Further, the interaction of these coated liposomes in comparison to their uncoated counterparts with myoblast cells is assessed. Their uptake/association efficiency with these cells is determined. Further, their dose-dependent cytotoxicity with and without entrapped hydrophobic cargo (thiocoraline) is characterized. Taken together, the reported results demonstrate the potential of PDA coated liposomes as a tool in biomedical applications.

Advanced mimics of cells require a large yet controllable number of subcompartments encapsulated within a scaffold, equipped with a trigger to initiate, terminate, and potentially restart an enzymatic reaction. Recently introduced capsosomes, polymer capsules containing thousands of liposomes, are a promising platform for the creation of artificial cells. Capsosomes are formed by sequentially layering liposomes and polymers onto particle templates, followed by removal of the template cores. Herein, we engineer advanced capsosomes and demonstrate the ability to control the number of subcompartments and hence the degree of cargo loading. To achieve this, we employ a range of polymer separation layers and liposomes to form functional capsosomes comprising multiple layers of enzyme-loaded liposomes. Differences in conversion rates of an enzymatic assay are used to verify that multilayers of intact enzyme-loaded liposomes are assembled within a polymer hydrogel capsule. The size-dependent retention of the cargo encapsulated within the liposomal subcompartments during capsosome assembly and its dependence on environmental pH changes are also examined. We further show that temperature can be used to trigger an enzymatic reaction at the phase transition temperature of the liposomal subcompartments, and that the encapsulated enzymes can be utilized repeatedly in several subsequent conversions. These engineered capsosomes with tailored properties present new opportunities en route to the development of functional artificial cells.

The formation of specific IgE, IgG1, and IgG4 antibodies was investigated by immunoblotting during hyposensitization with timothy grass-pollen extract and 6 years later, Until the end of immunotherapy, specific IgG antibody levels increased. Also simultaneously, the number of allergenic components detected by IgG increased. However, this IgG response was similar in responding and nonresponding patients; thus, it did not correlate with the clinical outcome of the therapy. More allergenic compounds were also detected by IgE on immunoblots, but again without correlation to success of therapy. Six years after immunotherapy, the therapeutic effect was still present, although by now the observed immunoglobulin-binding patterns were similar to patterns observed in the same patients' sera collected before the initiation of hyposensitization. Thus, changes of antibody-binding patterns in immunoblot do not relate to the success or failure of immunotherapy.

The formation of specific IgE, IgG1, and IgG4 antibodies was investigated by immunoblotting during hyposensitization with timothy grass-pollen extract and 6 years later, Until the end of immunotherapy, specific IgG antibody levels increased. Also simultaneously, the number of allergenic components detected by IgG increased. However, this IgG response was similar in responding and nonresponding patients; thus, it did not correlate with the clinical outcome of the therapy. More allergenic compounds were also detected by IgE on immunoblots, but again without correlation to success of therapy. Six years after immunotherapy, the therapeutic effect was still present, although by now the observed immunoglobulin-binding patterns were similar to patterns observed in the same patients' sera collected before the initiation of hyposensitization. Thus, changes of antibody-binding patterns in immunoblot do not relate to the success or failure of immunotherapy.