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Abstract Art and materials innovation have always been intertwined, dating back to the earliest human creations. In modern times, however, the increasing specialization of materials science often restricts artists' access to cutting‐edge materials. Here, the materials science aspects of an art‐science collaboration between artist Kimsooja and the Wiesner Lab at Cornell University, are detailed. The project involves the development of a custom‐made iridescent block copolymer coating by means of self‐assembly, originally applied to transparent window panels of a façade for the ≈14 m tall art installation:A Needle Woman: Galaxy Is a Memory, Earth is a Souvenirby artist Kimsooja. After several exhibitions in the US and Europe, the installation is now part of the permanent museum collection at Yorkshire Sculpture Park in Wakefield, UK. Full characterization of the solution blade‐cast coatings show shear aligned, standing up lamellar morphologies that behave as volume‐phase gratings with periodicities between 300 and 400 nm. Coatings are also applied to foldable (origami) paper and converted into iridescent porous ceramic materials. It is hoped this work inspires and informs communities across materials science, the arts, and architecture. 

Abstract Oral delivery, while a highly desirable form of nanoparticle‐drug administration, is limited by challenges associated with overcoming several biological barriers. Here, the authors study how fluorescent and poly(ethylene glycol)‐coated (PEGylated) core‐shell silica nanoparticles sized 5 to 50 nm interact with major barriers including intestinal mucus, intestinal epithelium, and stomach acid. From imaging fluorescence correlation spectroscopy studies using quasi‐total internal reflection fluorescence microscopy, diffusion of nanoparticles through highly scattering mucus is progressively hindered above a critical hydrodynamic size around 20 nm. By studying Caco‐2 cell monolayers mimicking the intestinal epithelia, it is observed that ultrasmall nanoparticles below 10 nm diameter (Cornell prime dots, [C’ dots]) show permeabilities correlated with high absorption in humans from primarily enhanced passive passage through tight junctions. Particles above 20 nm diameter exclusively show active transport through cells. After establishing C’ dot stability in artificial gastric juice, in vivo oral gavage experiments in mice demonstrate successful passage through the body followed by renal clearance without protein corona formation. Results suggest C’ dots as viable candidates for oral administration to patients with a proven pathway towards clinical translation and may generate renewed interest in examining silica as a food additive and its effects on nutrition and health. 

Abstract Nanostructured silver stands out among other plasmonic materials because its optical losses are the lowest of all metals. However, nanostructured silver rapidly degrades under ambient conditions, preventing its direct use in most plasmonic applications. Here, a facile and robust method for the preparation of highly stable nanostructured silver morphologies is introduced. 3D nanostructured gyroid networks are fabricated through electrodeposition into voided, self‐assembled triblock terpolymer scaffolds. Exposure to an argon plasma degraded the polymer and stabilized the silver nanostructure for many weeks, even in high humidity and under high‐dose UV irradiation. This stabilization protocol enables the robust manufacture of low‐loss silver nanostructures for a wide range of plasmonic applications. 

Abstract Solid polymer electrolytes for lithium batteries promise improvements in safety and energy density if their conductivity can be increased. Nanostructured block‐copolymer electrolytes specifically have the potential to provide both good ionic conductivity and good mechanical properties. This study shows that the previously neglected nanoscale composition of the polymer electrolyte close to the electrode surface has an important effect on impedance measurements, despite its negligible extent compared to the bulk electrolyte. Using standard stainless steel blocking electrodes, the impedance of lithium salt‐doped poly(isoprene‐b‐styrene‐b‐ethylene oxide) (ISO) exhibits a marked decrease upon thermal processing of the electrolyte. In contrast, covering the electrode surface with a low molecular weight poly(ethylene oxide) (PEO) brush results in higher and more reproducible conductivity values, which are insensitive to the thermal history of the device. A qualitative model of this effect is based on the hypothesis that ISO surface reconstruction at the different electrode surfaces leads to a change in the electrostatic double layer, affecting electrochemical impedance spectroscopy measurements. As a main result, PEO‐brush modification of electrode surfaces is beneficial for the robust electrolyte performance of PEO‐containing block‐copolymers and may be crucial for their accurate characterization and use in Li‐ion batteries.