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Abstract The arrangement of solvent molecules and ions at solid–liquid interfaces determines electrochemical properties that are important in separations platforms, sensing technologies, and energy‐storage systems. Here we show that single glass and polymer pores in contact with propylene carbonate (PC) solutions of LiClO₄exhibit an effective surface potential that is modulated by the enantiomeric excess of the solvent. In particular, electrochemical and electrokinetic measurements of ionic transport through glass pipettes and polymer pores reveal that the effective surface potential is significantly lower in solutions prepared using enantiomerically pure PC than in solutions prepared using racemic PC. Both pore systems became positively charged in all racemic solutions examined in the range of LiClO₄concentrations between 1 mM and 100 mM, whereas solutions in (R)‐(+)‐PC induced a positive surface potential only at concentrations above ~5 mM. The effective surface potential is quantified through asymmetry in current–voltage curves and zeta‐potential measurements. Vibrational sum‐frequency‐generation experiments on LiClO₄solutions in racemic and enantiomerically pure PC indicate that the surface lipid‐bilayer‐like region in the former is more strongly organized than in the latter, dictating the favorable positions for lithium and perchlorate ions in each case. The more ordered molecular packing in the racemic liquid leads to accumulation of lithium ions on the outside of the bilayer, creating a higher effective positive charge. Our results highlight the extreme sensitivity of the interfacial potential on molecular organization of the solvent, and the relatively unexplored role that chirality can play in electrokinetic phenomena. 

Abstract Nanotopographic surfaces are a powerful tool for studying and controlling cell behavior. However, the fabrication of nanotopographic master patterns using conventional photolithography is expensive, which limits the range of designs that can be explored. In this study, a method is demonstrated for the photoreshaping of large‐area patterns of nanoridges. The original master pattern is created using conventional lithography, and an azopolymer replica is prepared using soft lithography. The manipulation of the nanoridges is achieved by projecting light with specific polarizations and exposure times, resulting in controllable widening, buckling, or removal of the ridges. The reprogrammed azopolymer master patterns can then be replicated, creating reproducible new nanotopographies that can be transferred into other materials using a molding procedure. Diffraction can be used for in situ monitoring of the reprogramming during exposure. Image‐analysis methods are used to characterize buckled ridges as a function of exposure time. The response of MCF10A epithelial cells are investigated to buckled nanoridges. A substantial impact of buckling on the dynamics and location of actin polymerization, as well as on the distribution and lengths of contiguous polymerized regions is also observed. 

Significance Tumor progression to enable metastasis includes remodeling the wavy bundles of collagen making up the tissue stromal extracellular matrix (ECM) into straight bundles within the tumor microenvironment. While wavy collagen bundles are thought to be inhibitory to cell polarization and migration in tissue, straight ECM fibers are thought to be conducive, thereby mediating metastasis. We used nanofabricated cell culture substrates that mimic the ECM fiber waveforms seen in both benign- and metastases-promoting tumor ECMs. Large amplitude ECM waves depolarized tumor cells and decreased directional migration via cell contractility-mediated organization of the cytoskeleton and adhesions. Thus, ECM architecture of normal tissue and benign tumors may generally inhibit tumor cell exit, but this may be overcome by increasing tumor cell contractility.