Enhancing the robustness of functional biomacromolecules is a critical challenge in biotechnology, which if addressed would enhance their use in pharmaceuticals, chemical processing and biostorage. Here we report a novel method, inspired by natural biomineralization processes, which provides unprecedented protection of biomacromolecules by encapsulating them within a class of porous materials termed metal-organic frameworks. We show that proteins, enzymes and DNA rapidly induce the formation of protective metal-organic framework coatings under physiological conditions by concentrating the framework building blocks and facilitating crystallization around the biomacromolecules. The resulting biocomposite is stable under conditions that would normally decompose many biological macromolecules. For example, urease and horseradish peroxidase protected within a metal-organic framework shell are found to retain bioactivity after being treated at 80 °C and boiled in dimethylformamide (153 °C), respectively. This rapid, low-cost biomimetic mineralization process gives rise to new possibilities for the exploitation of biomacromolecules.

Within a polymer film, free-volume elements such as pores and channels typically have a wide range of sizes and topologies. This broad range of free-volume element sizes compromises a polymer's ability to perform molecular separations. We demonstrated free-volume structures in dense vitreous polymers that enable outstanding molecular and ionic transport and separation performance that surpasses the limits of conventional polymers. The unusual microstructure in these materials can be systematically tailored by thermally driven segment rearrangement. Free-volume topologies can be tailored by controlling the degree of rearrangement, flexibility of the original chain, and judicious inclusion of small templating molecules. This rational tailoring of free-volume element architecture provides a route for preparing high-performance polymers for molecular-scale separations.

The SAXS/WAXS beamline at the Australian Synchrotron is an advanced and flexible undulator X‐ray scattering beamline used for small‐ and wide‐angle X‐ray scattering analysis on a wide variety of solids, fluids and surfaces across a diverse range of research and development fields. The beamline has numerous features that minimize the intensity of the instrument background, provide automated stable optics, and allow accurate analysis of very weakly scattering samples. The geometric and intensity requirements of a three‐slit collimation system are described in detail for conventional metal and single‐crystal germanium slits. Straightforward ray tracing and simple linear projections describe the observed direct beam as well as parasitic background scattering geometry of the beamline at its longest camera length, providing a methodology for the design and operation of similar beamlines. As an aid to instrument design, the limit of background intensity determined by the intensity incident on single‐crystal germanium guard slit edges and its q dependence was quantified at 11 keV. Details of the beamline's implementation, underlying optical concept and measured performance are given.

The nanostructure of a series of 20 protic ionic liquids (PILs) has been investigated using small- and wide-angle X-ray scattering (SAXS and WAXS). The PILs contained alkylammonium, dialkylammonium, trialkylammonium, and cyclic ammonium cations combined with organic or inorganic anions. The presence of hydroxyl and methoxy substituents on the alkyl chains of the cations was also explored. Many of the PILs showed a nanostructure resulting from segregation of the polar and nonpolar components of the ionic liquid. It was found that this segregation was enhanced for longer alkyl chains, with a corresponding increase in the length scale, whereas the presence of hydroxyl groups on the alkyl chains led to much less ordered liquids. The broad range of protic ionic liquids studied allowed several structure-property relationships to be established. The solvophobic effect was shown to be dependent on the nanostructure of the PILs. These PILs support amphiphile self-assembly, and it was shown that the less structured PILs had more "water-like" behavior in the diversity of lyotropic liquid-crystal phases supported, and the thermal stability ranges for these phases.

Porosity loss, also known as physical aging, in glassy polymers hampers their long term use in gas separations. Unprecedented interactions of porous aromatic frameworks (PAFs) with these polymers offer the potential to control and exploit physical aging for drastically enhanced separation efficiency. PAF-1 is used in the archetypal polymer of intrinsic microporosity (PIM), PIM-1, to achieve three significant outcomes. 1) hydrogen permeability is drastically enhanced by 375% to 5500 Barrer. 2) Physical aging is controlled causing the selectivity for H2 over N2 to increase from 4.5 to 13 over 400 days of aging. 3) The improvement with age of the membrane is exploited to recover up to 98% of H2 from gas mixtures with N2 . This process is critical for the use of ammonia as a H2 storage medium. The tethering of polymer side chains within PAF-1 pores is responsible for maintaining H2 transport pathways, whilst the larger N2 pathways gradually collapse.

Phase contrast x-ray imaging of small animal lungs reveals a speckled intensity pattern not seen in other tissues, making the lungs highly visible in comparison to other organs. Although bearing a superficial resemblance to alveoli, the cause of this speckle has not been established. With a view to determining the mechanism for the formation of speckle, this paper details the results of propagation-based phase contrast experiments performed on mice lungs, together with packed glass microspheres used to emulate lung tissue. These experimental studies are compared to numerical simulations, based on wave propagation techniques. We find that speckle arises from focusing effects, with multiple alveoli acting as aberrated compound refractive lenses. Both experiments and modelling suggest that this speckle-formation phenomenon may lead to better screening methods for human lungs than conventional radiography.

Coflow is a new method for delivering radiation-sensitive biological and other solution-based samples to high-brightness X-ray beamlines that exploits laminar flow to ameliorate radiation-damage limitations and provides a host of practical improvements associated with these types of experiments.

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