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This article has a correction concerning the authors: We regret that there is an error with the author list in our original article. The authors Jussi Helminen, Paulus Hyväri, and Ilkka Kilpeläinen, all with the Department of Chemistry, University of Helsinki, P.O. Box 55, FI-00014 Helsinki, Finland, were mistakenly omitted. The author list should be as shown above in this Addition and Correction. DOI 10.1021/acssuschemeng.0c07773 Ioncell is a Lyocell based technology for the production of manmade cellulose fibers. This technology exploits the intrinsic dissolution power of superbase-based ionic liquids (ILs) toward cellulose and the ability to form spinnable cellulose solutions. The regenerated fibers are produced via a dry-jet wet spinning process in which the cellulose filaments are stretched in an air gap before regenerating in an aqueous coagulation medium. For the commercialization of this process, it is essential to demonstrate the quantitative recovery of the solvent from the coagulation bath without impairing its solvation power. This study reports on the spinnability and recyclability of the IL 7-methyl-1,5,7-triazabicyclo[4.4.0]dec-5-enium acetate ([mTBDH][OAc]) over five cycles in comparison to 1,5-diaza-bicyclo[4.3.0]non-5-enium acetate ([DBNH][OAc]). The aqueous IL solutions were recovered from the coagulation bath by successive thermal treatments under reduced pressure. Accordingly, the recycled ILs were utilized to dissolve 13 wt % cellulose pulp in each cycle without the addition of make-up IL. While using [mTBDH][OAc], the pulp was completely dissolved and processed into easily spinnable cellulose solutions during all five cycles, whereas the ability to dissolve pulp was completely lost after the first recovery cycle when using [DBNH][OAc]. The composition of the recovered ILs and extent of side-products generated in the adopted process was analyzed in detail. This includes characterization of the rheological properties of the solutions as well as the macromolecular and mechanical properties of the regenerated fibers. In addition, we review the toxicity of both solvents using Vibrio fischeri bacteria. Finally, the spun fibers from all [mTBDH][OAc] spinning trials were combined to produce a demonstration dress (Paju), designed and sewn by Marimekko Design House in Finland.

Publisher Copyright: © 2021 The Authors The potential of using capillary electromigration techniques for biomimicking essential biological interactions is described. The most commonly used methodologies with their exploitation in calculations of kinetics and biomolecular interaction data are briefly discussed. Experimental approaches for bimolecular interactions with some selected examples, including lipoproteins, glycosaminoglycan, liposomes and some DNA or RNA interactions, are enlighted including the affinity constants for some selective important interactions. The review demonstrates that capillary electromigration techniques can be used as alternative biomimicking tools for the determination of important biological interactions. This review covers selected papers published in 2003-2021.

Ionic liquids are used to dewater a suspension of birch Kraft pulp cellulose nanofibrils (CNF) and as a medium for water-free topochemical modification of the nanocellulose (a process denoted as “WtF-Nano”). Acetylation was applied as a model reaction to investigate the degree of modification and scope of effective ionic liquid structures. Little difference in reactivity was observed when water was removed, after introduction of an ionic liquid or molecular co-solvent. However, the viscoelastic properties of the CNF suspended in two ionic liquids show that the more basic, but non-dissolving ionic liquid, allows for better solvation of the CNF. Vibrio fischeri bacterial tests show that all ionic liquids in this study were harmless. Scanning electron microscopy and wide-angle X-ray scattering on regenerated samples show that the acetylated CNF is still in a fibrillar form. 1 D and 2 D NMR analyses, after direct dissolution in a novel ionic liquid electrolyte solution, indicate that both cellulose and residual xylan on the surface of the nanofibrils reacts to give acetate esters.

The use of bare fused silica capillary in CE can sometimes be inconvenient due to undesirable effects including adsorption of sample or instability of the EOF. This can often be avoided by coating the inner surface of the capillary. In this work, we present and characterize two novel polyelectrolyte coatings (PECs) poly(2-(methacryloyloxy)ethyl trimethylammonium iodide) (PMOTAI) and poly(3-methyl-1-(4-vinylbenzyl)-imidazolium chloride) (PIL-1) for CE. The coated capillaries were studied using a series of aq. buffers of varying pH, ionic strength, and compn. Our results show that the investigated polyelectrolytes are usable as semi-permanent (phys. adsorbed) coatings with at least five runs stability before a short coating regeneration is necessary. Both PECs showed a considerably decreased stability at pH 11.0. The EOF was higher using Good's buffers than with sodium phosphate buffer at the same pH and ionic strength. The thickness of the PEC layers studied by quartz crystal microbalance was 0.83 and 0.52 nm for PMOTAI and PIL-1, resp. The hydrophobicity of the PEC layers was detd. by anal. of a homologous series of alkyl benzoates and expressed as the distribution consts. Our result demonstrates that both PECs had comparable hydrophobicity, which enabled sepn. of compds. with log Po/w > 2. The ability to sep. cationic drugs was shown with β-blockers, compds. often misused in doping. Both coatings were also able to sep. hydrolysis products of the ionic liq. 1,5-diazabicyclo[4.3.0]non-5-ene acetate at highly acidic conditions, where bare fused silica capillaries failed to accomplish the sepn.

Lipidomics is an emerging field of science not only due to its integral part of cell biology and biophysics but also due to the key role of lipids in the modulation of membrane physical properties, signaling, and cell death regulation. The aim of this study was to characterize changes in N‐palmitoyl ceramide concentration and in the global lipid profile in macrophages challenged by oxidized low‐density lipoprotein and nutrient deprived hepatocytes. For this purpose, a quantitative targeted method based on gas chromatography‐mass spectrometry for the determination of total N‐palmitoyl ceramide concentrations in the cellular membranes of cells under stress was used. Ultrahigh‐performance liquid chromatography‐quadrupole‐time of flight mass spectrometry was applied for the comprehensive profiling of lipids. In essence, we found that both models of cellular stress caused an increase in N‐palmitoyl ceramide levels. In addition, increased levels of other ceramides were observed as well as up‐ and down‐regulation of several other lipid species.

The applicability of a polyelectrolyte, Elvacite 2669, as a pseudostationary phase in capillary electrokinetic chromatography for the separation of some neutral hydrophobic compounds was investigated. In addition, its behavior in buffer solutions for capillary electrophoretic separations was studied by dynamic light scattering. With the polymer concentration held constant and the methanol-water ratio varied, study was made of the viscosity, the migration times of some neutral hydrophobic compounds, and the light scattering properties of the buffers. The effect of varying the polymer concentration on the separation of the compounds was also investigated. All studies were made under basic conditions. Data on the aggregation behavior, including the size and aggregation number of the polyelectrolyte under different conditions, are given and the capillary electrophoretic results are interpreted in terms of the dynamic light scattering data. In addition, the interaction of Elvacite 2669 with the fused silica wall was investigated, and the results showed that polymer adsorption onto the capillary wall occurred at polymer concentrations at and above 0.5 wt%. Both the capillary electrophoretic and dynamic light scattering results showed the behavior of Elvacite 2669 to be highly dependent on the methanol-water ratio in the buffer.