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A systematic series of industrial‐relevant polystyrene‐based anion exchange resins that are functionalized with hydro‐ or fluorocarbon chains are compared regarding their adsorption behavior toward perfluorocarboxylic acids (PFCA) in respect to their charge, chain length, and type of chain. The results clearly show the dominance of electrostatic interactions in the adsorption process as uncharged adsorber materials showed no adsorption at all. In contrast, the charged adsorber materials showed in general a PFCA removal of 80% to 30% over the experiment depending on effluent fraction. Unexpectedly, for perfluorobutanoic acid (PFBA) the highest removal rate is found with consistently >90%. Despite observing significant benefits in the adsorption of PFCA for fluoroalkylated adsorbers in comparison to their non‐fluorinated counterparts, this effect of fluoroalkylation is comparatively small and can not be clearly attributed to fluorophilic interactions between the fluoroalkyl chains. These findings help clarifying that the introduction of fluorocarbon moieties in adsorber materials is not necessary in order to remove fluorocarbon molecules from the environment. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Mussel‐inspired coatings, known for their outstanding substrate‐independent adhesive capabilities, have numerous potential applications in materials science and biomedical fields. To improve the understanding of how these polymers' molecular structure and chemical composition affect their coating mechanisms and resulting coating properties, herein three mussel‐inspired polymers are developed: dendritic polyglycerol with 40% catechol groups and 60% amines (dPG40), linear polyglycerol with 80% catechols and 20% amines (lPG80), and finally lPG40 with 40% catechols and 60% amines. After a series of characterizations, it is found that chemical surface modification with a monolayer coating can be easily achieved with lPG40, and that robust and well‐defined nano‐ to micro‐structural surface coatings are possible with lPG80 and dPG40. Tunable properties are found to include not only coating speed, but coating thickness, roughness, and surficial topography. This diverse suite of controllable attributes enables mussel‐inspired polyglycerol (MiPG) coatings to satisfy a wide‐range of applications on multiple materials. [ABSTRACT FROM AUTHOR]

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‐NH2). 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 nm2. 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. [ABSTRACT FROM AUTHOR]

In this work, a one‐pot approach for the covalent functionalization of few‐layer black phosphorus (BP) by anionic ring opening polymerization of glycidol to obtain multifunctional BP‐polyglycerol (BP‐PG) with high amphiphilicity for near‐infrared‐responsive drug delivery and biocompatibility is reported. Straightforward synthesis in combination with exceptional biological and physicochemical properties designates functionalized BP‐PG as a promising candidate for a broad range of biomedical applications. [ABSTRACT FROM AUTHOR]

Here, we report a one-pot, straightforward, and efficient method for the covalent functionalization of black phosphorous (BP) nanosheets with biopolymers on a gram scale. l-lactide and glycidol monomers were stepwise copolymerized onto the surface of exfoliated BP resulting in highly water-soluble functional nanosheets (BP-PLA-PG). In contrast to pristine BP, their functionalized counterparts did not degrade under ambient conditions and were stable for several weeks. Owing to their stability, efficient photothermal effect, and low toxicity, BP-PLA-PG sheets were loaded with doxorubicin (DOX), and their anticancer effect was investigated in vitro and in vivo. The laser-triggered release of DOX, in combination with the photothermal effect of the functionalized BP sheets, manifested in strong antitumor effects in animal studies. One-pot straightforward functionalization, high loading capacity, low toxicity, excellent water dispersibility and stability, as well as high functionality, support BP-PLA-PG as a promising vector for the future biomedical applications, including targeted drug delivery and bioimaging. [ABSTRACT FROM AUTHOR]

Molybdenum disulfide (MoS2) holds great promise for antibacterial applications owing to its strong photothermal performance and biocompatibility. Most of its antibacterial explorations have sought enhanced antibacterial potency through designing new hybrid inorganic materials, the relationship between its physiochemical properties and antibacterial activities has yet to be explored. This work is the first to investigate the combination effects of different sized and functionalized MoS2 sheets on their antibacterial activities. The bacterial capture abilities of 3 µm mannosylated, galactosylated, and glucosylated sheets, as well as 300 nm mannosylated sheets, all with similar sugar densities, are compared. Only mannosylated MoS2 sheets are found to agglutinate normal Escherichia coli (E. coli) and large mannosylated MoS2 sheets show the strongest E. coli agglutination. Despite slightly weaker photothermal performance under near‐infrared (NIR) laser irradiation, large mannosylated MoS2 sheets exhibit higher antibacterial activity than the smaller sheets. By much stronger specific multivalent binding, large sheets capture E. coli more efficiently and compensate for their reduced photothermal activity. Besides providing a facile approach to eliminate E. coli bacteria, these findings offer valuable guidance for future development of 2D nanomaterial‐based antibacterial agents and filter holder materials, where large‐functionalized sheets can capture and eliminate bacteria powerfully. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Luminescent solar concentrators (LSC) allow to obtain renewable energy from building integrated photovoltaic systems. As promising efficient and long‐term stable LSC fluorophores semiconductor nanocrystals like quantum dots (QDs) with size and composition tunable optoelectronic properties have recently emerged. The most popular II/VI or IV/VI semiconductor QDs contain, however, potentially hazardous cadmium or lead ions, which is a bottleneck for commercial applications. A simple aqueous based, microwave‐assisted synthesis for environmentally friendly and highly emissive AgInS2/ZnS QDs is developed using 3‐mercaptopropionic acid (MPA) and glutathione (GSH) and their incorporation into polylaurylmethacrylate (PLMA) polymer slabs integrable in LSC devices (10.4 × 10.4 × 0.2 cm3, G = 12.98). With this simple approach, optical power efficiencies (OPE) of 3.8% and 3.6% and optical quantum efficiencies (OQE) of 24.1% and 27.4% are obtained, which are among the highest values yet reported. [ABSTRACT FROM AUTHOR]

Biofouling is a major challenge in the application of textiles, biosensors, and biomedical implants. In the current work, a straightforward method for the solvent‐free polymerization of antifouling dendritic polyglycerol (dPG) from mussel‐inspired dendritic polyglycerol (MI‐dPG) coatings on hydrophilic titanium dioxide (TiO2) and hydrophobic polydimethylsiloxane (PDMS) is reported. Surface characterization is performed by static water contact angle (CA) measurements, X‐ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM). Significant lower CA values are obtained after dPG grafting from MI‐dPG‐coated TiO2 and MI‐dPG coated PDMS. Furthermore, XPS shows a time‐dependent increase of the CO bond content upon dPG grafting from MI‐dPG‐coated TiO2 and MI‐dPG‐coated PDMS. Analysis of the surface morphology by SEM shows a clear time‐dependent increase in the surface roughness upon dPG grafting from MI‐dPG‐coated TiO2 and MI‐dPG‐coated PDMS. When the viability of two adhesive cell types is studied via LIVE/DEAD staining, a strong reduction in the cell density is observed after the dPG grafting from MI‐dPG‐coated TiO2 and MI‐dPG‐coated PDMS (a decrease of >95% in all cases). The combined results show that biocompatible but highly cell‐repelling surfaces are efficiently constructed via the grafting of dPG from MI‐dPG‐coated TiO2 and MI‐dPG‐coated PDMS. [ABSTRACT FROM AUTHOR]

Fluorous biphasic systems use the temperature-sensitive miscibility of fluorinated materials in nonfluorous solutions as a means to control reaction systems and easily separate catalysts or other compounds from a mixture. We present perfluoroalkylated nanographene as a viable platform for photohomogenization and recycling of fluorous-tagged catalysts. The photothermal properties of graphene materials, particularly in the near-infrared range, enable comparatively fast activation time and simplify the recycling of catalysts thanks to the easy separation of the solid fluorinated graphene phase from most solvents by centrifugation. A fluorinated phosphine catalyst was used in a modified, catalyst-regenerative Appel reaction as a model system. The catalyst could be successfully recovered and reused for at least 10 cycles with minimal loss of yield. [ABSTRACT FROM AUTHOR]

Mucus is the first defense barrier against viruses in the human immune system. Inspired by the mucus structure, we designed a highly sulfated hydrogel to bind viruses and prevent infection of the underlying cells. The hydrogel was formed by gelation of sulfated cellulose nanofiber (SCNF) with Ca 2+ . SCNF exhibited a mucin-like nanofiber structure with high numbers of sulfated groups. Based on the electrostatic interactions with a virus, SCNF could efficiently inhibit herpes simplex virus-1 (HSV-1) infection with a half-maximal inhibitory concentration (IC 50 ) of 0.43 μg/mL, which is comparable to that of heparin (IC 50 = 0.30 μg/mL). Benefiting from the multiporous structure and sulfate groups, the Ca 2+ -SCNF hydrogel could efficiently trap HSV-1 and inhibit the virus from attacking the underlying cells in a transwell model. Furthermore, SCNF also inhibited SARS-CoV-2 infection in a similar experimental setting. By integrating the advantages of high and broad-spectrum virus inhibitory activity as well as low toxicity, it is believed that the Ca 2+ -SCNF hydrogel can promote the development of highly biocompatible and efficient antiviral material with "binding and inhibition" capability and other diverse strategies.