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In this study, an ionic liquid (IL), 1-butyl-3-methylimidazolium acetate, was used to prepare ionogels with microcrystalline cellulose (MCC) and halloysite (Hal). SEM, XRD, TG, DSC, FTIR spectroscopy, conductometry and mechanical tests were used to study the morphology, structure, thermal behaviour and electrophysical and mechanical characteristics of synthesised ionogels. XRD analysis showed a slight decrease in the interlayer space of halloysite in ionogels containing MCC, which may have been associated with the removal of residual water molecules resulting from hydrophilic IL anions and polymer macromolecules. A change in conductivity and glass-transition temperature of the ionic liquid was revealed due to intercalation into halloysite (a confinement effect) and modification with cellulose. For triple IL/Hal/MCC ionogels, the characteristic thermal degradation temperatures were higher than the corresponding values for IL/Hal composites. This indicates that the synthesised IL/Hal/MCC ionogels are characterised by a greater thermal stability than those of IL/Hal systems.

The electrorheological (ER) effect was experimentally observed in dielectric suspensions containing tungsten oxide (WO3) modified with surfactant molecules (sodium dodecyl sulfate (SDS) and dodecylamine (DDA)) in electric fields up to several kilovolts per millimeter. The dielectric properties of WO3 suspensions in silicone oil were analyzed, depending on the frequency of the electric field, in the range from 25 to 106 Hz. Unmodified WO3 suspensions, as well as suspensions modified with sodium dodecyl sulfate, were shown to exhibit a positive electrorheological effect, whereas suspensions modified with dodecylamine demonstrated a negative electrorheological effect. The quantitative characteristics of the negative electrorheological effect in the strain−compression and shear regimes were obtained for the first time. Visualization experiments were performed to see the chain structures formed by WO3 particles modified with sodium dodecyl sulfate, as well as for dynamic electroconvection in electrorheological fluids containing WO3 modified with dodecylamine. The negative electrorheological effect was shown to be associated with the processes of phase separation in the electric field, which led to a multiplicative effect and a strong electroconvection of the suspension at field strengths above 1 kV/mm.

Although diabetes mellitus is known to be a disease associated with mitochondrial dysfunction, not everything is clear about mitochondrial Ca2+ transport and Ca2+-induced permeability transition in diabetic cells. The objective of this work was to study the operation of MCU and Ca2+-dependent mitochondrial permeabilization in the liver cells of Sprague-Dawley rats under the streptozotocin-induced type I diabetes. It was shown that two weeks after the induction of diabetes, the rate of Ca2+ uptake by the mitochondria of diabetic animals increased ~1.4-fold. The expression of MCU and MICU1 subunits did not change, yet the quantity of dominant-negative MCUb channel subunits was almost twice as lower. The organelles also became more resistant to the induction of CsA-sensitive MPT pore and less resistant to the induction of CsA-insensitive palmitate/Ca2+-induced pore. The mitochondria of diabetic liver cells also showed changes in the lipid matrix of their membranes. The content of fatty acids in the membranes grew, and microviscosity of the lipid bilayer (assessed with laurdan) increased. At the same time, lipid peroxidation (assessed by the production of malonic dialdehyde) was stimulated. The paper discusses the consequences of the diabetes-related changes in mitochondria in the context of cell physiology.

Spherical cellulose nanocrystal-based hybrids grafted with titania nanoparticles were successfully produced for topical drug delivery. The conventional analytical filter paper was used as a precursor material for cellulose nanocrystals (CNC) production. Cellulose nanocrystals were extracted via a simple and quick two-step process based on first the complexation with Cu(II) solution in aqueous ammonia followed by acid hydrolysis with diluted H2SO4. Triclosan was selected as a model drug for complexation with titania and further introduction into the nanocellulose based composite. Obtained materials were characterized by a broad variety of microscopic, spectroscopic, and thermal analysis methods. The drug release studies showed long-term release profiles of triclosan from the titania based nanocomposite that agreed with Higuchi model. The bacterial susceptibility tests demonstrated that released triclosan retained its antibacterial activity against Escherichia coli and Staphylococcus aureus. It was found that a small amount of titania significantly improved the antibacterial activity of obtained nanocomposites, even without immobilization of model drug. Thus, the developed hybrid patches are highly promising candidates for potential application as antibacterial agents.