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Gel polymer electrolytes composed of deep eutectic solvent acetamide 4 :Zn(TFSI) 2 and poly(ethylene oxide) (PEO) are prepared by using a fast, solvent-free procedure. The effect of the PEO molecular weight and its concentration on the physicochemical and electrochemical properties of the electrolytes are studied. Gels prepared with ultrahigh molecular-weight PEO present pseudo-solid behavior and ionic conductivity even higher than that of the original liquid electrolyte. A decrease in the dendritic growth in soft gels with PEO contents up to 1 wt % is demonstrated. The changes in the chemical structure of the electrolyte produced by the strong interactions between ethylene oxide units and Zn 2+ have also been studied. The addition of PEO takes the electrolyte out of its original eutectic composition, producing blend crystallization. However, it is possible to retain the eutectic point of the electrolyte in a gel form if the addition of PEO is accompanied by the reduction of acetamide., (© 2023 The Authors. ChemSusChem published by Wiley-VCH GmbH.)

The performance of rechargeable magnesium batteries is strongly dependent on the choice of electrolyte. The desolvation of multivalent cations usually goes along with high energy barriers, which can have a crucial impact on the plating reaction. This can lead to significantly higher overpotentials for magnesium deposition compared to magnesium dissolution. In this work we combine experimental measurements with DFT calculations and continuum modelling to analyze Mg deposition in various solvents. Jointly, these methods provide a better understanding of the electrode reactions and especially the magnesium deposition mechanism. Thereby, a kinetic model for electrochemical reactions at metal electrodes is developed, which explicitly couples desolvation to electron transfer and, furthermore, qualitatively takes into account effects of the electrochemical double layer. The influence of different solvents on the battery performance is studied for the state-of-the-art magnesium tetrakis(hexafluoroisopropyloxy)borate electrolyte salt. It becomes apparent that not necessarily a whole solvent molecule must be stripped from the solvated magnesium cation before the first reduction step can take place. For Mg reduction it seems to be sufficient to have one coordination site available, so that the magnesium cation is able to get closer to the electrode surface. Thereby, the initial desolvation of the magnesium cation determines the deposition reaction for mono-, tri- and tetraglyme, whereas the influence of the desolvation on the plating reaction is minor for diglyme and tetrahydrofuran. Overall, we can give a clear recommendation for diglyme to be applied as solvent in magnesium electrolytes., (© 2021 The Authors. ChemSusChem published by Wiley-VCH GmbH.)

This article presents the results of experiments, which examine cell mechanisms with the goal of confirming the effective action of the active ingredients used in anti-aging cosmetics. Skin stiffness measurements with the use of an atomic force microscope on two forms of vitamin C (ascorbyl tetraisopalmitate and l-ascorbic acid) have been presented. The estimated Young's modulus for three types of cells (a control as well as cells treated with two forms of vitamin C) has shown significant differences in the stiffness of the tested cells which was confirmed in the histological staining experiment. The presented results indicate the dependence between collagen synthesis and the stiffness of cells treated with two forms of vitamin C., (© 2019 Wiley Periodicals, Inc.)

One promising strategy to reconstruct bone defects relies on 3D printed porous structures. In spite of several studies having been carried out to fabricate controlled, interconnected porous constructs, the control over surface features at, or below, the microscopic scale remains elusive for 3D polymeric scaffolds. In this study, we developed and refined a methodology which can be applied to homogeneously and reproducibly modify the surface of polymeric 3D printed scaffolds. We have demonstrated that the combination of a polymer solvent and the utilization of ultrasound was essential for achieving appropriate surface modification without damaging the structural integrity of the construct. The modification created on the scaffold profoundly affected the macroscopic and microscopic properties of the scaffold with an increased roughness, greater surface area, and reduced hydrophobicity. Furthermore, to assess the performance of such materials in bone tissue engineering, human mesenchymal stem cells (hMSC) were cultured in vitro on the scaffolds for up to 7 days. Our results demonstrate a stronger commitment toward early osteogenic differentiation of hMSC. Finally, we demonstrated that the increased in the specific surface area of the scaffold did not necessarily correlate with improved adsorption of protein and that other factors, such as surface chemistry and hydrophilicity, may also play a major role.

In this research, the effect of the presence of living cells (SaOS-2) on in vitro degradation of Mg-2.0Zn-0.98Mn (ZM21) magnesium alloy was examined by two methods simple immersion/cell culture tests and electrochemical measurements (electrochemical impedance spectroscopy and potentiodynamic polarization) under cell culture conditions. In immersion/cell culture tests, when SaOS-2 cells were cultured on ZM21 samples, pH of cell culture medium decreased, therefore weight loss and Mg 2+ ion release from the samples increased. Electrochemical measurements revealed the presence of living cells increased corrosion rate (I corr ) and decreased polarization resistance (R p ) after 48h of incubation. This acceleration of ZM21 corrosion can mainly be attributed to the decrease of medium pH due to cellular metabolic activities., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Four kinds of biodegradable polymers were employed to prepare bioresorbable coatings on Mg-2.0Zn-0.98Mn (ZM21) alloy to understand the relationship between polymer characteristics, protective effects on substrate corrosion, cytocompatibility and cell functionality. Poly-l-lactide (PLLA), poly(3-hydroxybutyrate) (PHB), poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) or poly(lactic-co-glycolic) acid (PLGA) was spin-coated on ZM21, obtaining a smooth, non-porous coating less than 0.5μm in thickness. Polymer coating characterization, a degradation study, and biocompatibility evaluations were performed. After 4 w of immersion into cell culture medium, degradation of PLGA and PLLA coatings were confirmed by ATR-FTIR observation. The coatings of PLLA, PHB and PHBV, which have lower water permeability and slower degradation than PLGA, provide better suppression of initial ZM21 degradation and faster promotion of human osteosarcoma cell growth and differentiation., (Copyright © 2016 Elsevier B.V. All rights reserved.)