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Boron clusters are applied in medicinal chemistry because of their high stability in biological environments and intrinsic ability to capture neutrons. However, their intermolecular interactions with lipid membranes, which are critical for their cellular delivery and biocompatibility, have not been comprehensively investigated. In this study, we combine different experimental methods – Langmuir monolayer isotherms at the air–water interface, calorimetry (DSC, ITC), and scattering techniques (DLS, SAXS) – with MD simulations to evaluate the impact of closo‐dodecaborate clusters on model membranes of different lipid composition. The cluster anions interact strongly with zwitterionic membranes (POPC and DPPC) via the chaotropic effect and cause pronounced expansions of lipid monolayers. The resulting lipid membranes contain up to 33 mol % and up to 52 weight % of boron cluster anions even at low aqueous cluster concentrations (1 mM). They show high (μM) affinity to the hydrophilic‐hydrophobic interface, affecting the structuring of the lipid chains, and therefore triggering a sequence of characteristic effects: (i) an expansion of the surface area per lipid, (ii) an increase in membrane fluidity, and (iii) a reduction of bilayer thickness. These results aid the design of boron cluster derivatives as auxiliaries in drug design as well as transmembrane carriers and help rationalize potential toxicity effects. [ABSTRACT FROM AUTHOR]

In living systems, protein assemblies have essential functions, serving as structural supports, transport highways for molecular cargo, and containers of genetic material. The construction of protein assemblies, which involves control over space and time, remains a significant challenge in biotechnology. Here, we show that anionic boron clusters, 3,3′‐commo‐bis[closo‐1,2‐dicarba‐3‐cobaltadodecaborane] (COSAN−), and halogenated closo‐dodecarboranes (B12X122−, X=H, Cl, or I), described as super‐chaotropic nano‐ions, induce the formation of 2D assemblies of model proteins, myoglobin, carbonic anhydrase, and trypsin inhibitor. We found that the nano‐ion concentration reversibly controls the size of the protein assemblies. Furthermore, the secondary structures of the proteins are only slightly affected by assembly formation. For myoglobin, the formation of these assemblies even prevents temperature denaturation, highlighting a preservation effect of nano‐ions. Our study reveals that inorganic boron‐based nano‐ions act as a reversible molecular glue for proteins, providing a potential starting point for the further development of controlled protein assemblies. [ABSTRACT FROM AUTHOR]

Supramolecular polymers built from stimuli‐responsive host‐guest interactions represent an attractive way of tailoring smart materials. Herein, we exploit the chaotropic effect of polyoxometalates and related host‐guest properties to design unconventional polymer systems with reversible redox and thermo‐responsive sol‐gel transition. These supramolecular networks result from the association of cyclodextrin‐based oligomers and Keggin‐type POMs acting as electro‐active crosslinking agents. The structure and the dynamics of such self‐assembly systems have been investigated using a multiscale approach involving MALDI‐TOF, viscosity measurements, cyclic voltammetry, 1H‐NMR (1D and DOSY), and Small‐Angle X‐ray Scattering. Our results reveal that the chaotropic effect corresponds to a powerful and efficient force that can be used to induce responsiveness in hybrid supramolecular oligomeric systems. [ABSTRACT FROM AUTHOR]

In cosmetics, there is some interest to solubilized polar antioxidant molecules in oil. This is a matrix that can indeed protect these fragile molecules against oxidation and that makes possible the polar antioxidants transfer through the epidermis in order to be delivered within the dermis. Varying the oil formulation allows the achievement of a high content of antioxidants in a natural vegetable oil using an oleo-eco extraction process. However, it was necessary to characterize this content using quantitative and efficient methods such as High-Performance Thin-Layer Chromatography technique. The aim of this work was to develop a method of antioxidant’s characterization with this technique without a preliminary re-extraction of the antioxidants.