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Abstract Every animal secretes mucus, placing them among the most diverse biological materials. Mucus hydrogels are complex mixtures of water, ions, carbohydrates, and proteins. Uncertainty surrounding their composition and how interactions between components contribute to mucus function complicates efforts to exploit their properties. There is substantial interest in commercializing mucus from the garden snail,Cornu aspersum, for skincare, drug delivery, tissue engineering, and composite materials.C. aspersumsecretes three mucus—one shielding the animal from environmental threats, one adhesive mucus from the pedal surface of the foot, and another pedal mucus that is lubricating. It remains a mystery how compositional differences account for their substantially different properties. Here, we characterize mucus proteins, glycosylation, ion content, and mechanical properties that could be used to provide insight into structure-function relationships through an integrative “mucomics” approach. We identify macromolecular components of these hydrogels, including a previously unreported protein class termed Conserved Anterior Mollusk Proteins (CAMPs). Revealing differences betweenC. aspersummucus shows how considering structure at all levels can inform the design of mucus-inspired materials. 

Abstract The solution rheology of a fully synthetic, monodisperse mucin that mimics the glycosylated domains of natural mucins, poly(β‐Gal‐Thr)₂₂, is studied to systematically explore relationships between polymer structure, solution conditions, and rheological properties. Using standard cone‐plate rheometry, shear thinning is observed over a range of concentrations, with an apparent yield stress—typical for gels—evident at the highest concentrations. This is surprising given the dilute, weakly interacting nature of the solutions and the lack of observable structure in cryogenic electron microscopy and particle tracking microrheology. However, interfacial rheometry demonstrates that the gel‐like behavior is attributable to a thin structured layer at the air–water interface, without any bulk gelation. This is attributed to an interfacial layer formed by inter‐mucin H‐bonds that yields when sheared. A computational model using kinetic Monte Carlo (kMC) simulations qualitatively reproduces the yield stress response of such a network through an intermolecular bonding potential. An analytical model of stochastic bond formation and breaking, validated by the kMC simulations, demonstrates that having multiple bonding sites per mucin with a force‐dependent debonding rate aligns with experiments, consistent with intermolecular interactions for other mucin proteins. This suggests that in mucin solutions, gelation may begin at the air–water interface, and emphasizes the need for multitechnique validation when exploring structural cues of mucus gelation through rheometry. 

Abstract The challenge of fabricating transparent and conductive (T/C) films and patterns for applications in flexible electronics, touch screens, solar cells, and smart windows remains largely unsolved. Traditional fabrication techniques are complex, costly, time‐consuming, and struggle to achieve the necessary precision and accuracy over electronic and optical properties. Here, hypersurface photolithography (HP), which integrates microfluidics, a digital micromirror device, and photochemical surface‐initiated polymerizations is used to create polymer brush patterns. The high‐throughput optimization enabled by HP provides conditions to fabricate patterns composed of cross‐linked polymer brushes containing Au‐binding 2‐vinylpyrrolidine (2VP) groups with precise control over the height and the composition at each pixel. Au nanoparticles (AuNPs) are incorporated into the polymer brush patterns through in situ reduction of Au ions, resulting in T/C composite AuNP/polymer brush patterns. The sheet resistance at 100 mA of a 2VP‐AuNP‐functionalized patterns on a glass substrate is 0.42 Ω sq⁻¹with 86% transmittance of visible light. Additional patterns demonstrate multiplexing by copatterning rhodamine B functionalized fluorescent polymer brushes and AuNP/polymer brush conductive domains. This work solves the challenge of creating T/C films by forming metal‐polymer composites from polymer brush patterns, offering a scalable solution for electronic and optical device development and fabrication. 

Abstract A photochemical printer, equipped with a digital micromirror device (DMD), leads to the rapid elucidation of the kinetics of the surface‐initiated atom‐transfer radical photopolymerization ofN,N‐dimethylacrylamide (DMA) andN‐isopropylacrylamide (NIPAM) monomers. This effort reveals conditions where polymer brushes of identical heights can be grown from each monomer. With these data, hidden images are created that appear upon heating the substrate above the lower critical solution temperature (LCST) of polyNIPAM. By introducing a third monomer, methacryloxyethyl thiocarbamoyl rhodamine B, a second, orthogonal image appears upon UV‐irradiation. With these studies, it is shown how a new photochemical printer accelerates discovery, creates arbitrary patterns, and addresses long‐standing problems in brush polymer and surface chemistry. With this technology in hand a new method is demonstrated to encrypt data within hypersurfaces.