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Membranes with special functionalities, such as self-cleaning, especially those for oil/water separation, have attracted much attention due to their wide applications. However, they are difficult to recycle and reuse after being damaged. Herein, we put forward a new N-substituted polyurethane membrane concept with self-healing ability to address this challenge. The membrane obtained by electrospinning has a self-cleaning surface with an excellent self-healing ability. Importantly, by tuning the membrane composition, the membrane exhibits different wettability for effective separation of oil/water mixtures and water-in-oil emulsions, whilst still displaying a self-healing ability and durability against damage. To the best of our knowledge, this is the first report to demonstrate a self-healing membrane for oil/water separation, which provides the fundamental research for the development of advanced oil/water separation materials.

The purpose of this work was to evaluate the usefulness of silicone hydrogel contact lenses loaded with ketotifen fumarate for ocular drug delivery. First, silicone contact lenses were prepared by photopolymerization of bitelechelic methacrylated polydimethylsiloxanes macromonomer, 3-methacryloxypropyltris(trimethylsiloxy)silane, and N,N-dimethylacrylamide using ethylene glycol dimethacrylate as a cross-linker and Darocur 1173 as an initiator followed by surface plasma treatment. Then, the silicone hydrogel matrices of the contact lenses were characterized by equilibrium swelling ratio (ESR), tensile tests, ion permeability, and surface contact angle. Finally, the contact lenses were loaded with ketotifen fumarate by pre-soaking in drug solution to evaluate drug loading capacity, in vitro and in vivo release behavior of the silicone contact lenses. The results showed that ESR and ion permeability increase, and the surface contact angle and tensile strength decreased with the increase of DMA component in the silicone hydrogel. The drug loading and in vitro releases were dependent on the hydrogel composition of hydrophilic/hydrophobic phase of the contact lenses. In rabbit eyes, the pre-soaked contact lenses sustained ketotifen fumarate release for more than 24 h, which leads to a more stable drug concentration and a longer mean retention time in tear fluid than that of eye drops of 0.05%.

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Nanocomposites have attracted more attention due to their extensive applications. However, it is still a huge technological challenge in fabrication of transparent hybrid materials because of nanoparticle aggregation resulting from their high specific surface energies. In this paper polymerizable molecule was controlled chemically grafted onto ZnS nanoparticles to obtain polymerizable-group-capped nanoparticles that can copolymerize with a mixture of acrylic monomers of N,N-dimethyl­acrylamide (DMA) and 2-hydroxyethyl methacrylate (HEMA) or glycidyl methacrylate (GMA) or methyl methacrylate (MMA) to prepare transparent high refractive index (RI) nanocomposite hydrogels. The dispersion homogeneity of the nanoparticles in the nanocomposites was studied by dynamic mechanical thermal analysis (DTMA), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and energy dispersive X-ray mapping analysis (EDX). Moreover, the nanocomposites were characterized by transmittance, mechanical properties, and refractive index (RI). The results showed that grafted amount of polymerizable group on the nanoparticle surface influences the cross-link density and microphase structure of the resultant nanocomposites, leading to different transmittance and mechanical properties. The RI of hydrated and dry nanocomposites can be regulated to a peak value of 1.652 and 1.751, respectively, by a simple adjustment of ZnS content in the nanocomposites. Our approach was also proved to be effective in preparing DMA-free transparent nanocomposites with high RI of 1.824 by copolymerizing between polymerizable-group-capped ZnS and single monomer of HEMA or GMA or MMA.