Thermoresponsive poly(2-oxazoline)s, polypeptoids, and polypeptides

This review covers the recent advances in the emerging field of thermoresponsive polyamides or polymeric amides, i.e., poly(2-oxazoline)s, polypeptoids, and polypeptides, with a specific focus on structure-thermoresponsive property relationships, self-assembly, and applications

Stable covalently photo-cross-linked poly(ionic liquid) membrane with gradient pore size

An imidazolium-based poly(ionic liquid) is covalently cross-linked via UV light-induced thiolene (click) chemistry to yield a stable porous polyelectrolyte membrane with gradients of crosslink density and pore size distribution along its cross-section.Comment: 16 pages, 10 figure

Multivariate Imaging for Fast Evaluation of In Situ Dark Field Microscopy Hyperspectral Data

Dark field scattering microscopy can create large hyperspectral data sets that contain a wealth of information on the properties and the molecular environment of noble metal nanoparticles. For a quick screening of samples of microscopic dimensions that contain many different types of plasmonic nanostructures, we propose a multivariate analysis of data sets of thousands to several hundreds of thousands of scattering spectra. By using non-negative matrix factorization for decomposing the spectra, components are identified that represent individual plasmon resonances and relative contributions of these resonances to particular microscopic focal volumes in the mapping data sets. Using data from silver and gold nanoparticles in the presence of different molecules, including gold nanoparticle-protein agglomerates or silver nanoparticles forming aggregates in the presence of acrylamide, plasmonic properties are observed that differ from those of the original nanoparticles. For the case of acrylamide, we show that the plasmon resonances of the silver nanoparticles are ideally suited to support surface enhanced Raman scattering (SERS) and the two-photon excited process of surface enhanced hyper Raman scattering (SEHRS). Both vibrational tools give complementary information on the in situ formed polyacrylamide and the molecular composition at the nanoparticle surface.Caroline von Humboldt Professorship of HUPeer Reviewe

Biomineralization of engineered spider silk protein-based composite materials for bone tissue engineering

Materials based on biodegradable polyesters such as poly(butylene terephthalate) (PBT) or poly(butylene terephthalate-co-poly(alkylene glycol) terephthalate) (PBTAT) have potential application as pro-regenerative scaffolds for bone tissue engineering. Herein is reported the preparation of films composed of PBT or PBTAT and an engineered spider silk protein, (eADF4(C16)), that displays multiple carboxylic acid moieties capable of binding calcium ions and facilitating their biomineralization with calcium carbonate or calcium phosphate. Human mesenchymal stem cells cultured on films mineralized with calcium phosphate show enhanced levels of alkaline phosphatase activity suggesting that such composites have potential use for bone tissue engineering

Search for quark contact interactions and extra spatial dimensions using dijet angular distributions in proton-proton collisions at √s = 8 TeV

A search is presented for quark contact interactions and extra spatial dimensions in proton-proton collisions at s = 8 TeV using dijet angular distributions. The search is based on a data set corresponding to an integrated luminosity of 19.7 -1 collected by the CMS detector at the CERN LHC. Dijet angular distributions are found to be in agreement with the perturbative QCD predictions that include electroweak corrections. Limits on the contact interaction scale from a variety of models at next-to-leading order in QCD corrections are obtained. A benchmark model in which only left-handed quarks participate is excluded up to a scale of 9.0 (11.7) TeV for destructive (constructive) interference at 95% confidence level. Lower limits between 5.9 and 8.4 TeV on the scale of virtual graviton exchange are extracted for the Arkani-Hamed-Dimopoulos-Dvali model of extra spatial dimensions

Facile Photochemical Modification of Silk Protein–Based Biomaterials

Silk protein–based materials show promise for application as biomaterials for tissue engineering. The simple and rapid photochemical modification of silk protein–based materials composed of either Bombyx mori silkworm silk or engineered spider silk proteins (eADF4(C16)) is reported. Radicals formed on the silk‐based materials initiate the polymerization of monomers (acrylic acid, methacrylic acid, or allylamine) which functionalize the surface of the silk materials with poly(acrylic acid) (PAA), poly(methacrylic acid) (PMAA), or poly(allylamine) (PAAm). To demonstrate potential applications of this type of modification, the polymer‐modified silks are mineralized. The PAA‐ and PMAA‐functionalized silks are mineralized with calcium carbonate, whereas the PAAm‐functionalized silks are mineralized with silica, both of which provide a coating on the materials that may be useful for bone tissue engineering, which will be the subject of future investigations

Sol‐Gel‐Derived Ordered Mesoporous High Entropy Spinel Ferrites and Assessment of Their Photoelectrochemical and Electrocatalytic Water Splitting Performance

The novel material class of high entropy oxides with their unique and unexpected physicochemical properties is a candidate for energy applications. Herein, it is reported for the first time about the physico‐ and (photo‐) electrochemical properties of ordered mesoporous (CoNiCuZnMg)Fe₂O₄ thin films synthesized by a soft‐templating and dip‐coating approach. The A‐site high entropy ferrites (HEF) are composed of periodically ordered mesopores building a highly accessible inorganic nanoarchitecture with large specific surface areas. The mesoporous spinel HEF thin films are found to be phase‐pure and crack‐free on the meso‐ and macroscale. The formation of the spinel structure hosting six distinct cations is verified by X‐ray‐based characterization techniques. Photoelectron spectroscopy gives insight into the chemical state of the implemented transition metals supporting the structural characterization data. Applied as photoanode for photoelectrochemical water splitting, the HEFs are photostable over several hours but show only low photoconductivity owing to fast surface recombination, as evidenced by intensity‐modulated photocurrent spectroscopy. When applied as oxygen evolution reaction electrocatalyst, the HEF thin films possess overpotentials of 420 mV at 10 mA cm⁻² in 1 m KOH. The results imply that the increase of the compositional disorder enhances the electronic transport properties, which are beneficial for both energy applications

Bioinspired Poly(2-oxazoline)s

Poly(2-oxazoline)s are regarded as pseudopeptides, thus bioinspired polymers, due to their structural relationship to polypeptides. Materials and solution properties can be tuned by varying the side-chain (hydrophilic-hydrophobic, chiral, bioorganic, etc.), opening the way to advanced stimulus-responsive materials and complex colloidal structures. The bioinspired “smart” solution and aggregation behavior of poly(2-oxazoline)s in aqueous environments are discussed in this review