Here, L. H. Urner and co-workers identify a new detergent design strategy for the non-denaturing structural analysis of membrane proteins by studying the gas-phase properties of azobenzene-based oligoglycerol detergents.

The ability to design amphiphiles with predictable solubility properties is of everlasting interest in supramolecular chemistry. Relevant structural parameters include the hydrophobic–hydrophilic balance and structural flexibility. In this work, we investigate the water solubility of azobenzene‐based triglycerol bolaamphiphiles (TGBAs). In particular, we analyzed the structural effects of backbone hydrophobicity, flexibility, and cis/trans isomerization on the water solubility of a subset of five TGBAs. This leads to the first example of a non‐ionic bolaamphiphile whose water solubility can be changed by irradiation with light. The underlying kinetics were monitored using liquid chromatography and a closer analysis of the underlying aggregation processes provides a mechanistic understanding of the light‐driven dissolution process. We anticipate that the results obtained will help to engineer bolaamphiphiles with predictable solution properties in the future.

A simple and robust method is presented to immobilize a heparin‐analog polyelectrolyte on inert hydrophobic surfaces. It is demonstrated that an amphiphilic block copolymer consisting of linear polyglycerol sulfate (lPGS) and a benzophenone modified anchor block can be bound to polystyrene surfaces in a facile dip‐coating procedure. The chaotropic salt guanidinium chloride is used to overcome the aggregation of the polymer as well as the repulsion between highly hydrated sulfate groups and the polystyrene surface. Irradiation with UV light tethers the polymer chains covalently to the surface. The resulting coating exhibits an aggregate morphology that resembles the aggregation behavior in solution, with a coating thickness of 8 nm. The behavior of the surfaces is dominated by the polyelectrolyte brush coating. They swell and collapse in response to different ionic strengths of the surrounding medium, and bind proteins via electrostatic interactions. The coating is stable toward physiological conditions over the course of several weeks. Coated surfaces bind to proteins of the complement cascade when in contact with dilute blood serum, which results in a decrease of complement activity to 78 ± 4%. The coating procedure can also be applied to other nonactivated polymer surfaces, as demonstrated on a polypropylene fleece.

Wearing face masks during pandemics is an important protective measure against the spreading of virus‐related infectious diseases. Nevertheless, the risk of indirect transmission of virus by handling masks is one of the earliest concerns. This problem can be minimized by supplementing the masks’ textile structure with virus protective coatings. Therefore, in this concept, suitable techniques for manufacturing virus protective filter media should be evaluated. In this study, nonwoven polyamide 6 (PA6) filter material is functionalized with negatively charged linear polyglycerol sulfate (LPGS) as a virus binding functional group. Two coating conditions are investigated in which the direct covalent coating with LPGS has emerged as the optimum coating method, showing no damage to the PA6 nanofiber structure. The uncoated PA6 and LPGS‐coated PA6 filter materials exhibited virus particle filtration efficiencies of 95% and 94% for airborne feline coronavirus, 98% and 86% for airborne equine herpesvirus 1(EHV‐1), respectively. However, the SARS‐CoV‐2 absorption assay in solution indicates that the LPGS coating reduces viral titres up to 71% when incubating with the LPGS‐coated PA6 filter media for one‐hour. Thus, such an effect is not seen for uncoated PA6 materials. These findings confirm the suitability of LPGS coating as a suitable platform for suppression the spreading of viruses in different pandemics.

The adsorption of viruses from aqueous solution is frequently performed to detect viruses. Charged filtration materials capture viruses via electrostatic interactions, but lack the specificity of biological virus-binding substances like heparin. Herein, we present three methods to immobilize heparin-mimicking, virus-binding polymers to a filter material. Two mussel-inspired approaches are used, based on dopamine or mussel-inspired dendritic polyglycerol, and post-functionalized with a block-copolymer consisting of linear polyglycerol sulfate and amino groups as anchor (lPGS-b-NH 2 ). As third method, a polymer coating based on lPGS with benzophenone anchor groups is tested (lPGS-b-BPh). All three methods yield dense and stable coatings. A positively charged dye serves as a tool to quantitatively analyze the sulfate content on coated fleece. Especially lPGS-b-BPh is shown to be a dense polymer brush coating with about 0.1 polymer chains per nm 2 . Proteins adsorb to the lPGS coated materials depending on their charge, as shown for lysozyme and human serum albumin. Finally, herpes simplex virus type 1 (HSV-1) and severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) can be removed from solution upon incubation with coated fleece materials by about 90% and 45%, respectively. In summary, the presented techniques may be a useful tool to collect viruses from aqueous environments.