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Hydrogels are significant hydrophilic materials with 3D polymeric network structures, which have received much attention in recent decades. DNA-based hydrogel materials have been widely used for tissue engineering, biosensors, bioanalysis, and clinical therapy on their excellent stability, bioanalysis, biocompatibility, and programmability. The addition of functional DNA (deoxyribonucleic acid) sequences, such as DNAzymes or aptamers, are embedded in polymer networks, which expand the additional molecular recognition capabilities and sensibility of smart DNA hydrogels. In particular, targeting-responsive DNA hydrogels have attracted much attention and provided a portable, sensitive, selective, and visualised detection platform for biosensors. In this review, the latest applications of distinct types of DNA hydrogel biosensors for detection in various fields are introduced. Then, the prospects for future development trends and challenges of DNA-based hydrogel materials for biosensing are given. [ABSTRACT FROM AUTHOR]

In this study, the solvent-free polyacrylonitrile (PAN) microspheres were successfully fabricated using an easily -assembled double-T emulsion generator. The effects of removing solvent methods and CO2 replacing period during the supercritical drying on the PAN microspheres were ascertained. As suggested from the experimental results, the supercritical drying method could more effectively remove solvent than the vacuum drying and solvent washing. After the supercritical drying, the sphericity of PAN microspheres remained, and the percentage contraction was less than 5%. By Stereomicroscope, Field Emission Scanning Electron Microscope (FESEM), energy dispersive X-ray analysis (EDS), confocal microscope as well as white light interferometer, the solvent-free PAN microspheres structures were characterized. There was a trace amount of Si after treatment, whereas it was found to be almost removed, which satisfies the experiment requirements. By contrasting the results of the treatments with different CO2 replacing periods in the supercritical drying, the replacing period of 2 h was found as the optimal condition. In the future, the solvent-free PAN microspheres will have a potential application in the inertial confinement fusion experiment. [ABSTRACT FROM AUTHOR]

Extreme ultraviolet (EUV), 13.5 nm, lithography techniques have attracted a great deal of attention because of the mass production of 50 nm critical dimensions as the future generation lithography. One of key issues to be clarified for the development of a 13.5 nm EUV light source is to improve the conversion efficiency (CE). In this paper, hollow multilayer nanofibers were fabricated through the combination of a layer-by-layer (LBL) technique with the electrospinning technique. The obtained hollow fibers were employed as EUV targets. In order to improve the CE, the irradiated laser energy was increased from 1010 to 1011 W/cm2 and the CE was correspondingly increased from 0.43 to 0.83%. [ABSTRACT FROM AUTHOR]

Hollow capsules formed by layer-by-layer self-assembly polymers have been intensively studied for their potential applications in medicine and biotechnology. We have controlled such capsules' permeability with a hydrogen-bonding layer. Scanning electron microscopy and Fourier transform infrared results showed the fabrication of multilayer polyelectrolyte films. Z-potential results were employed to record the deposition of the polyelectrolyte. The diffusion coefficients for 6-carboxyfluorescein (6-CF) and fluorescently labeled goat anti-human IgG-FITC molecules passing through the wall were calculated based on the fluorescence recovery after photobleaching experiment. The results show that 6-CF molecules can pass through the capsule wall more easily than IgG-FITC molecules. By decreasing the solution's pH, the capsule's permeability to macromolecular dyes or small molecular dyes can be controlled, i.e., the capsule's permeability can be tuned by the hydrogen-bonding interaction. [ABSTRACT FROM AUTHOR]