Search for: All records

Abstract Nature‐inspired functional surfaces with micro‐ and nanoscale features have garnered interest for potential applications in optics, imaging, and sensing. Traditional fabrication methods, such as lithography and self‐assembly, face limitations in versatility, scalability, and morphology control. This study introduces an innovative technology, condensed droplet polymerization (CDP), for fabricating polymeric micro‐ and nano‐dome arrays (PDAs) with readily tunable geometric properties—a challenging feat for conventional methods. The CDP process leverages free‐radical polymerization in condensed monomer droplets, allowing rapid production of PDAs with targeted sizes, radii of curvature, and surface densities by manipulating a key synthesis parameter: the temperature of a filament array that activates initiators. This work systematically unravels its effects on polymerization kinetics, viscoelastic properties of the polymerizing droplets, and geometric characteristics of the PDAs. Utilizing in situ digital microscope, this work reveals the morphological evolution of the PDAs during the process. The resulting PDAs exhibit distinct optical properties, including magnification that enables high‐resolution imaging beyond the diffraction limit of conventional microscopes. This work demonstrates the ability to magnify and focus light, enhancing imaging of subwavelength structures and biological specimens. This work advances the understanding of polymerization mechanisms in nano‐sized reactors (i.e., droplets) and paves the way for developing compact optical imaging and sensing technologies. 

Abstract Chemical permeation enhancers (CPEs) represent a prevalent and safe strategy to enable noninvasive drug delivery across skin‐like biological barriers such as the tympanic membrane (TM). While most existing CPEs interact strongly with the lipid bilayers in the stratum corneum to create defects as diffusion paths, their interactions with the delivery system, such as polymers forming a hydrogel, can compromise gelation, formulation stability, and drug diffusion. To overcome this challenge, differing interactions between CPEs and the hydrogel system are explored, especially those with sodium dodecyl sulfate (SDS), an ionic surfactant and a common CPE, and those with methyl laurate (ML), a nonionic counterpart with a similar length alkyl chain. Notably, the use of ML effectively decouples permeation enhancement from gelation, enabling sustained delivery across TMs to treat acute otitis media (AOM), which is not possible with the use of SDS. Ciprofloxacin and ML are shown to form a pseudo‐surfactant that significantly boosts transtympanic permeation. The middle ear ciprofloxacin concentration is increased by 70‐fold in vivo in a chinchilla AOM model, yielding superior efficacy and biocompatibility than the previous highest‐performing formulation. Beyond improved efficacy and biocompatibility, this single‐CPE formulation significantly accelerates its progression toward clinical deployment.