Discovery of novel biphenyl-sulfonamide analogues as NLRP3 inflammasome inhibitors.

The aberrant activation of NLRP3 inflammasome has been observed in various human diseases. Targeting the NLRP3 protein with small molecule inhibitors shows immense potential as an effective strategy for disease intervention. Herein, a series of novel biphenyl-sulfonamide NLRP3 inflammasome inhibitors were designed and synthesized. The representative compound H28 was identified as potent and specific NLRP3 inflammasome inhibitor with IC50 values of 0.57 µM. Preliminary mechanistic studies have revealed that compound H28 exhibits direct binding to the NLRP3 protein (KD: 1.15 µM), effectively inhibiting the assembly and activation of the NLRP3 inflammasome. The results in a mouse acute peritonitis model revealed that H28 effectively inhibit the NLRP3 inflammasome pathway, demonstrating their anti-inflammatory properties. Our findings strongly support the further development of H28 as potential lead compound for treating NLRP3-related diseases.

Flexible Symmetric-Defection Antenna with Bending and Thermal Insensitivity for Miniaturized UAV.

Flexible conformal-enabled antennas have great potential for various developable surface-built unmanned aerial vehicles (UAVs) due to their superior mechanical compliance as well as maintaining excellent electromagnetic features. However, it remains a challenge that the antenna holds bending and thermal insensitivity to negligibly shift resonant frequency during conformal attachment and aerial flight, respectively. Here, we report a flexible symmetric-defection antenna (FSDA) with bending and thermal insensitivity. By engraving a symmetric defection on the reflective ground, the radiated unit attached to the soft polydimethylsiloxane (PDMS) makes the antenna resonate at the ISM microwave band (resonant frequency = 2.44 GHz) and conformal with a miniaturized UAV. The antenna is also insensitive to both the bending-conformal attachment (20 mm < r < 70 mm) and thermal radiation (20~100 °C) due to the symmetric peripheral-current field along the defection and the low-change thermal effect of the PDMS, respectively. Therefore, the antenna in a non-bending state almost keeps the same impedance matching and radiation when it is attached to a cylinder-back of a UAV. The flexible antenna with bending and thermal insensitivity will pave the way for more conformal or wrapping applications.

Design of a Low-Frequency Dielectrophoresis-Based Arc Microfluidic Chip for Multigroup Cell Sorting.

Dielectrophoresis technology is applied to microfluidic chips to achieve microscopic control of cells. Currently, microfluidic chips based on dielectrophoresis have certain limitations in terms of cell sorting species, in order to explore a microfluidic chip with excellent performance and high versatility. In this paper, we designed a microfluidic chip that can be used for continuous cell sorting, with the structural design of a curved channel and curved double side electrodes. CM factors were calculated for eight human healthy blood cells and cancerous cells using the software MyDEP, the simulation of various blood cells sorting and the simulation of the joule heat effect of the microfluidic chip were completed using the software COMSOL Multiphysics. The effect of voltage and inlet flow velocity on the simulation results was discussed using the control variables method. We found feasible parameters from simulation results under different voltages and inlet flow velocities, and the feasibility of the design was verified from multiple perspectives by measuring cell movement trajectories, cell recovery rate and separation purity. This paper provides a universal method for cell, particle and even protein sorting.

Polarization-dependent reconfigurable light field manipulation by liquid-immersion metasurface.

Traditional grating lenses can accumulate phase for adjusting wavefronts, and plasmonic resonances can be excited in metasurfaces with discrete structures for optical field modulation. Diffractive and plasma optics have been developing in parallel, with easy processing, small size, and dynamic control advantages. Due to theoretical hybridization, structural design can combine advantages and show great potential value. Changing the shape and size of the flat metasurface can easily produce light field reflections, but changes in height are rarely cross-explored. We propose a graded metasurface with a single-structure periodic arrangement, which can mix the effects of plasmonic resonance and grating diffraction. As for solvents of different polarities, strong polarization-dependent beam reflections are produced, enabling versatile beam convergence and deflection. Dielectric/metal nanostructures with selective hydrophobic/hydrophilic properties can be arranged by the structural material specification to selectively settle the location of the solution in a liquid environment. Furthermore, the wetted metasurface is actively triggered to achieve spectral control and initiate polarization-dependent beam steering in the broadband visible light region. Actively reconfigurable polarization-dependent beam steering has potential applications in tunable optical displays, directional emission, beam manipulation and processing, and sensing technologies.

Application and realization of Norland optical adhesive 73 novel photosensitive macromolecular material for the rapid preparation of periodically tunable nanoscale gratings.

Periodically tunable nano-gratings have an irreplaceable role in spectral scanning and optical communication, but the performance of gratings manufactured from different materials varies considerably, and the development of superior materials has energized the preparation of high-precision devices. This paper presents a nanoscale preparation process based on Norland Optical Adhesive 73 (NOA73), which enables the rapid preparation of periodically tunable nano-gratings with up to 100% light transmission. The powerful fluidity and shear rate of NOA73 make it uniquely suited to the preparation of precision devices, allowing the production of up to dense grating structures and offering the possibility of making nanoscale gratings. This paper uses multi-angle hierarchical lithography, die stretching, and replication to achieve further improvements in accuracy and successfully prepare gratings with a period of 500 nm. The successful preparation of NOA73 nano-gratings demonstrates the practicality of NOA73 as a material for precision device fabrication.

Review of Flexible Wearable Sensor Devices for Biomedical Application.

With the development of cross-fertilisation in various disciplines, flexible wearable sensing technologies have emerged, bringing together many disciplines, such as biomedicine, materials science, control science, and communication technology. Over the past few years, the development of multiple types of flexible wearable devices that are widely used for the detection of human physiological signals has proven that flexible wearable devices have strong biocompatibility and a great potential for further development. These include electronic skin patches, soft robots, bio-batteries, and personalised medical devices. In this review, we present an updated overview of emerging flexible wearable sensor devices for biomedical applications and a comprehensive summary of the research progress and potential of flexible sensors. First, we describe the selection and fabrication of flexible materials and their excellent electrochemical properties. We evaluate the mechanisms by which these sensor devices work, and then we categorise and compare the unique advantages of a variety of sensor devices from the perspective of in vitro and in vivo sensing, as well as some exciting applications in the human body. Finally, we summarise the opportunities and challenges in the field of flexible wearable devices.

Switching the Optical Chirality in Magnetoplasmonic Metasurfaces Using Applied Magnetic Fields.

Chiral nanophotonic devices are promising candidates for chiral molecule sensing, polarization of diverse nanophotonics, and display technologies. Active chiral nanophotonic devices, where the optical chirality can be controlled by an external stimulus has triggered great research interest. However, efficient modulation of the optical chirality has been challenging. Here, we demonstrate switching of the extrinsic chirality by applied magnetic fields in a magnetoplasmonic metasurface device based on a magneto-optical oxide material, Ce1Y2Fe5O12 (Ce:YIG). Due to the low optical loss and strong magneto-optical effect of Ce:YIG, we experimentally demonstrated giant and continuous far-field circular dichroism (CD) modulation by applied magnetic fields from -0.6 ± 0.2° to +1.9 ± 0.1° at 950 nm wavelength under glancing incident conditions. The far-field CD modulation is due to both magneto-optical circular dichroism and near-field modulation of the superchiral fields by applied magnetic fields. Finally, we demonstrate magnetic-field-tunable chiral imaging in millimeter-scale magnetoplasmonic metasurfaces fabricated using self-assembly.

Effect of oxygen stoichiometry on the structure, optical and epsilon-near-zero properties of indium tin oxide films.

Transparent conductive oxide (TCO) films showing epsilon near zero (ENZ) properties have attracted great research interest due to their unique property of electrically tunable permittivity. In this work, we report the effect of oxygen stoichiometry on the structure, optical and ENZ properties of indium tin oxide (ITO) films fabricated under different oxygen partial pressures. By using spectroscopic ellipsometry (SE) with fast data acquisition capabilities, we observed modulation of the material index and ENZ wavelength under electrostatic gating. Using a two-layer model based on Thomas-Fermi screening model and the Drude model, the optical constants and Drude parameters of the ITO thin films are determined during the gating process. The maximum carrier modulation amplitude ΔN of the accumulation layer is found to vary significantly depending on the oxygen stoichiometry. Under an electric field gate bias of 2.5 MV/cm, the largest ENZ wavelength modulation up to 27.9 nm at around 1550 nm is observed in ITO thin films deposited with oxygen partial pressure of P O 2 =10 Pa. Our work provides insights to the optical properties of ITO during electrostatic gating process for electro-optic modulators (EOMs) applications.

Enhanced Second Harmonic Generation from Ferroelectric HfO2-Based Hybrid Metasurfaces.

Integrated nonlinear metasurfaces leading to high-efficiency optical second harmonic generation (SHG) are highly desirable for optical sensing, imaging, and quantum photonic systems. Compared to traditional metal-only metasurfaces, their hybrid counterparts, where a noncentrosymmetric nonlinear photonic material is incorporated in the near-field of a metasurface, can significantly boost SHG efficiency. However, it is difficult to integrate such devices on-chip due to material incompatibilities, thickness scaling challenges, and the narrow band gaps of nonlinear optical materials. Here, we demonstrate significantly enhanced SHG in on-chip integrated metasurfaces by using nanometer thin films of ferroelectric Y:HfO2. This material has the merit of CMOS compatibility, ultraviolet transparency up to 250 nm, and significant scalability down to sub-10 nm when deposited on silicon. We observe a 20-fold magnitude enhancement of the SHG intensity from the hybrid metasurface compared to a bare ferroelectric HfO2 thin film. Moreover, a 3-fold SHG enhancement is observed from the hybrid metasurface compared to a control structure using nonferroelectric HfO2, demonstrating a major contribution to the SHG signal from ferroelectric Y:HfO2. The effective second-order nonlinear optical coefficient χ(2) of Y:HfO2 is determined to be 6.0 ± 0.5 pm/V, which is comparable to other complex nonlinear photonic oxide materials. Our work provides a general pathway to build an efficient on-chip nanophotonic nonlinear light source for SHG using ferroelectric HfO2 thin films.