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Abstract Mesenchymal–epithelial transition (MET) is essential for tissue and organ development and is thought to contribute to cancer by enabling the establishment of metastatic lesions. Despite its importance in both health and disease, there is a lack of in vitro platforms to study MET and little is known about the regulation of MET by mechanical cues. Here, hyaluronic acid‐based hydrogels with dynamic and tunable stiffnesses mimicking that of normal and tumorigenic mammary tissue are synthesized. The platform is then utilized to examine the response of mammary epithelial cells and breast cancer cells to dynamic modulation of matrix stiffness. Gradual softening of the hydrogels reduces proliferation and increases apoptosis of breast cancer cells. Moreover, breast cancer cells exhibit temporal changes in cell morphology, cytoskeletal organization, and gene expression that are consistent with mesenchymal–epithelial plasticity as the stiffness of the matrix is reduced. A reduction in matrix stiffness attenuates the expression of integrin‐linked kinase, and inhibition of integrin‐linked kinase impacts proliferation, apoptosis, and gene expression in cells cultured on stiff and dynamic hydrogels. Overall, these findings reveal intermediate epithelial/mesenchymal states as cells move along a matrix stiffness‐mediated MET trajectory and suggest an important role for matrix mechanics in regulating mesenchymal–epithelial plasticity. 

Abstract All‐solid‐state batteries have the potential for enhanced safety and capacity over conventional lithium ion batteries, and are anticipated to dominate the energy storage industry. As such, strategies to enable recycling of the individual components are crucial to minimize waste and prevent health and environmental harm. Here, we use cold sintering to reprocess solid‐state composite electrolytes, specifically Mg and Sr doped Li₇La₃Zr₂O₁₂with polypropylene carbonate (PPC) and lithium perchlorate (LLZO−PPC−LiClO₄). The low sintering temperature allows co‐sintering of ceramics, polymers and lithium salts, leading to re‐densification of the composite structures with reprocessing. Reprocessed LLZO−PPC−LiClO₄exhibits densified microstructures with ionic conductivities exceeding 10⁻⁴ S/cm at room temperature after 5 recycling cycles. All‐solid‐state lithium batteries fabricated with reprocessed electrolytes exhibit a high discharge capacity of 168 mA h g⁻¹at 0.1 C, and retention of performance at 0.2 C for over 100 cycles. Life cycle assessment (LCA) suggests that recycled electrolytes outperforms the pristine electrolyte process in all environmental impact categories, highlighting cold sintering as a promising technology for recycling electrolytes. 

Abstract Thermogels that exhibit a sol‐gel transition at body temperature represent a promising class of injectable biomaterials for biomedical applications. Thermogels reported thus far are generally composed of amphiphilic block copolymer micelles with an isotropic thermosensitive surface that induces intermicellar aggregation upon heating. Despite the promise, these hydrogels exhibit low mechanical strengths due to their uncontrollable aggregation resulting in void formation. To gain better control over intermicellar assembly, herein a novel thermogel design concept is presented based on patchy polymeric micelles bearing multiple thermosensitive surface domains. These domains serve as “patches” to bridge the micelles to form a percolated network structure. Patchy micelles are prepared from a binary mixture of amphiphilic block copolymers: Poly(N‐acryloylmorpholine)‐b‐poly(N‐benzylacrylamide) (PAM‐PBzAM) and poly (N‐isopropyl acrylamide)‐b‐poly(N‐benzylacrylamide) (PNIPAM‐PBzAM), where PBzAM, PAM and PNIPAM are the hydrophobic, hydrophilic and thermosensitive blocks, respectively. At 25 °C, the polymers self‐assembled into mixed shell micelles having a phase‐separated shell with PAM‐ and PNIPAM‐rich domains. At 37 °C, the PNIPAM domains undergo a hydrophilic‐to‐hydrophobic transition to induce intermicellar assembly into entangled worm‐like structures resulting in hydrogel formation. Patchy micelles form a homogeneous network structure without voids. The micelle design significantly affects the inter‐micellar assembly, the thermogelling behavior, and the mechanical properties of the hydrogels. 

Abstract The glass transition temperature (T_g) is a key property that dictates the applicability of conjugated polymers. TheT_gdemarks the transition into a brittle glassy state, making its accurate prediction for conjugated polymers crucial for the design of soft, stretchable, or flexible electronics. Here we show that a single adjustable parameter can be used to build a relationship between theT_gand the molecular structure of 32 semiflexible (mostly conjugated) polymers that differ drastically in aromatic backbone and alkyl side chain chemistry. An effective mobility value,ζ, is calculated using an assigned atomic mobility value within each repeat unit. The only adjustable parameter in the calculation ofζis the ratio of mobility between conjugated and non-conjugated atoms. We show thatζcorrelates strongly to theT_g, and that this simple method predicts theT_gwith a root-mean-square error of 13 °C for conjugated polymers with alkyl side chains. 

Abstract Here, a polymer blend active layer that exhibits both electronic and adhesive properties is introduced. Various conjugated polymers are blended with a catechol‐based polymer that shows high adhesion, such that blends serve as the active layer of multifunctional sticky organic thin‐film transistors (OTFTs). Blend films maintain relatively constant field‐effect charge carrier mobility in OTFTs regardless of composition. Lap shear adhesion strength tests show that all blend films exhibit adhesive properties with adhesion values ranging from 0.05 to 4.30 MPa. With relatively consistent mobility and the presence of adhesive properties at different compositions, blends of conjugated and adhesive polymers can lead to next‐generation organic transistors for stable 3D stacking and waterproof adhesive sensors. 

Abstract Hydrogen sulfide (H₂S) is a gaseous signaling molecule in the human body and has attracted attention in cancer therapy due to its regulatory roles in cancer cell proliferation and migration. Accumulating evidence suggests that continuous delivery of H₂S to cancer cells for extended periods of time suppresses cancer progression. However, one major challenge in therapeutic applications of H₂S is its controlled delivery. To solve this problem, polymeric micelles are developed containing H₂S donating‐anethole dithiolethione (ADT) groups, with H₂S release profiles optimal for suppressing cancer cell proliferation. The micelles release H₂S upon oxidation by reactive oxygens species (ROS) that are present inside the cells. The H₂S release profiles can be controlled by changing the polymer design. Furthermore, the micelles that show a moderate H₂S release rate exert the strongest anti‐proliferative effect in human colon cancer cells in in vitro assays as well as the chick chorioallantoic membrane cancer model, while the micelles do not affect proliferation of human umbilical vein endothelial cells. This study shows the importance of fine‐tuning H₂S release profiles using a micelle approach for realizing the full therapeutic potential of H₂S in cancer treatment. 

Abstract Nature has evolved several elegant strategies to organize inert building blocks into adaptive supramolecular structures. Favored among these is interfacial self‐assembly, where the unique environment of liquid–liquid junctions provides structural, kinetic, thermodynamic, and chemical properties that are distinct from the bulk solution. Here, antithetical fluorous–water interfaces are exploited to guide the assembly of non‐canonical fluorinated amino acids into crystalline mechanomorphogenic films. That is, the nanoscale order imparted by this strategy yields self‐healing materials that can alter their macro‐morphology depending on exogenous mechanical stimuli. Additionally, like natural biomolecules, organofluorine amino acid films respond to changes in environmental ionic strength, pH, and temperature to adopt varied secondary and tertiary states. Complementary biophysical and biochemical studies are used to develop a model of amino acid packing to rationalize this bioresponsive behavior. Finally, these films show selective permeability, capturing fluorous compounds while allowing the free diffusion of water. These unique capabilities are leveraged in an exemplary application of the technology to extract perfluoroalkyl substances from contaminated water samples rapidly. Continued exploration of these materials will advance the understanding of how interface‐templated and fluorine‐driven assembly phenomenon a can be co‐utilized to design adaptive molecular networks and living matter.