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Compared with the Caucasians, the Chinese had a thinner ciliary body and a more anteriorly positioned lens, which may contribute to more anteriorly positioned ciliary processes in this population. These findings might help to explain the higher prevalence of angle closure in the Chinese.

conditions to maintain the scale of medical device manufacturing; and 4) the treatment must not incorporate antibiotics to maintain global antimicrobial stewardship efforts. The zwitterionic polymer polysulfobetaine (PSB) was selected as the antifouling component of the surface modification to benefit from its biocompatibility, ultralow-fouling properties, and oxidative stability. By adsorbing water electrostatically, PSB coatings form a thin hydration barrier that prevents organic materials from adhering to surfaces. [22] Commonly used approaches to attach PSB coatings to surfaces, such as radical-initiated graft polymerizations of PSB-methacrylate necessitate the use of oxygen-free conditions, [23] preconditioning steps, [24] or long reaction times [25] that do not meet scalability requirements. To circumvent the use of air-free graft polymerizations, we employ perfluorophenylazide (PFPA) chemistry as a molecular anchor to link the PSB coatings onto the surfaces of polymeric materials under ambient conditions. When triggered with UV-light, PFPA moieties generate a highly reactive nitrene that forms covalent bonds with materials containing amines, CC double bonds, and CH bonds. [26,27] With this method, PSB is rapidly coated onto a broad range of substrates using UV light under ambient conditions with no preconditioning steps. Thus, many different medical devices may be quickly and conveniently treated on the manufacturing level.We first demonstrate the effect of the treatment on polydimethylsiloxane (PDMS) as an exemplary, extremely difficultto-modify model for a common elastomer used in implantable medical devices. [28] Commonly known as silicone, PDMS is widely used for its biocompatibility, good chemical stability, ease of fabrication using injection molding or extrusion, and low cost. [29][30][31] Many implantable device makers have moved away from classical medical elastomers and plastics such as latex and polyvinyl chloride due to allergens [32] or plasticizers [33] in these materials that leach out and often lead to irritation or complications. PDMS-based devices do not require plasticizers and have been shown to lead to fewer complications than latex and polyurethane-based devices. [34] Despite its ideal properties, the nonpolar nature of PDMS facilitates the adhesion of organic materials. Bacteria, platelets, proteins, and other biomolecules bind strongly to the hydrophobic surfaces of PDMS elastomers, leading to the colonization and proliferation of biofilms. [22] When common hydrophilic surface treatments are performed on PDMS, such as plasma oxidation, [35] UV-ozone, [36] or corona discharge, [37] the effects are short-term due to rapid hydrophobic recovery. The highly mobile chains of PDMS (glass transition temperature ≈ −120 °C) can reorient themselves to "hide" the surface modified elastomers, when exposed to air, within hours. [38] Other methods seeking long-lasting hydrophilic PDMS surfaces typically require preconditioning steps with silane [39][40][41] chemistry or radical polymerization. [...

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For the past 30 years, thin-film membrane composites have been the state-of-the-art technology for reverse osmosis, nanofiltration, ultrafiltration, and gas separation. However, traditional membrane casting techniques, such as phase inversion and interfacial polymerization, limit the types of material that are used for the membrane separation layer. Here, we describe a novel thin-film liftoff (T-FLO) technique that enables the fabrication of thin-film composite membranes with new materials for desalination, organic solvent nanofiltration, and gas separation. The active layer is cast separately from the porous support layer, allowing for the tuning of the thickness and chemistry of the active layer. A fiber-reinforced, epoxy-based resin is then cured on top of the active layer to form a covalently bound support layer. Upon submersion in water, the cured membrane lifts off from the substrate to produce a robust, freestanding, asymmetric membrane composite. We demonstrate the fabrication of three novel T-FLO membranes for chlorine-tolerant reverse osmosis, organic solvent nanofiltration, and gas separation. The isolable nature of support and active-layer formation paves the way for the discovery of the transport and selectivity properties of new polymeric materials. This work introduces the foundation for T-FLO membranes and enables exciting new materials to be implemented as the active layers of thin-film membranes, including high-performance polymers, two-dimensional materials, and metal–organic frameworks.