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RT2X2 compounds (R: rare compound; T: transition metals, X: Si, Ge), especially Ce-based compounds are important platforms for studying novel phenomena including magnetic behaviors, heavy Fermi superconductors, or the Knodo effect. Here, we report the growth of large-size CeCr2Si2C bulk single crystals with high purity, high quality, low defects, and high stability from high-temperature solution, laying a solid foundation for studying its native novel properties. Interestingly, native ferromagnetic behavior with a transition temperature of ∼12.4 K is first observed in CeCr2Si2C bulk single crystals confirmed by magnetic susceptibility and specific heat measurements. The ferromagnetic behavior originates from a long-range RKKY (Ruderman–Kittel–Kasuya–Yosida) magnetic exchange interaction mainly induced by the spatially localized f-electrons of Ce, along with d-electrons of Cr. Our findings elucidate the native ferromagnetic behavior of CeCr2Si2C bulk single crystals and widen the region of properties of RT2X2 compounds. [ABSTRACT FROM AUTHOR]

We report the results of long-time (80 h) growth of 4-inch SiC single crystals from solutions of C–Si–Cr–Ce with and without Al addition (5 at%) by a top seeded solution growth (TSSG) method aiming at clarifying the role of interfacial energy between SiC and liquid solution. The Al addition smooths the growth surface by suppressing step bunching and two-dimensional (2D) nucleation, improves the crystalline quality, stabilizes the 4H polytype, and changes the ingot shape. Importantly, the growth rate is more than two factors enhanced by adding Al to the solution in comparison with the solution free of Al. The substantial curbs of step bunching and 2D nucleation on the advancing surface of SiC are responsible for the enhancement of the growth rate. The interfacial energy of SiC/solution is found to decrease upon Al addition based on the in situ contact angle measurements of solution droplets on SiC (0001¯) at 1750 °C and 1850 °C for the first time. Our results clearly verify the effect of Al on the SiC growth from solutions and highlight the importance of solid/liquid interfacial energy anisotropy on the growth of SiC by TSSG. [ABSTRACT FROM AUTHOR]

Developing radical oxygen species (ROS)-generating nanoreactors as new "antibiotics" is a promising strategy for the treatment of multidrug-resistant (MDR) biofilm infections. Herein, we designed and fabricated silver nanoparticle-decorated calcium peroxide (CaO2) nanoreactors (CPA) for combating MDR biofilms. CPA could locally boost ROS production as oxidative stress amplifiers in a pH-triggered and self-catalytic manner in acidic biofilms, where H2O2 was released by the hydrolysis of CaO2 and sequentially catalyzed by Ag NPs in situ to generate O2˙−, thereby efficiently disrupting mature biofilms and killing bacteria. [ABSTRACT FROM AUTHOR]

We report a new biofunctionalized nanoplatform based on hyaluronic acid-coated gold-nano-dot-decorated hollow carbon nanospheres (AuHCNs-HA) for microRNA imaging in living cells. Importantly, the HA-coated nanoplatform could be internalized into target cells via CD44 receptor-mediated endocytosis. It can be further applied for intracellular miR-21 imaging in CD44-positive colorectal cancer cells. [ABSTRACT FROM AUTHOR]

Non-adherent cells play key roles in various biological processes. Studies on this type of cell, especially at single-cell resolution, help reveal molecular mechanisms underlying many biological and pathological processes. The emerging microfluidics technology has developed effective methods for analyzing cells. However, it remains challenging to treat and monitor single live non-adherent cells in an in situ, long-term, and real-time manner. Herein, a microfluidic platform was set up to generate and anchor cell-laden water-in-oil-in-water (W/O/W) double emulsions (DEs) to investigate these cells. Within the device, W/O/W DEs encapsulating non-adherent cells were generated through two adjacent flow-focusing structures and subsequently anchored in an array of microchambers. These droplets maintained the W/O/W structure and the anchorage status in the continuous perfusion fluid for at least one week. The mass transfer of different molecules with suitable molecular weights and partition coefficients between the interior and exterior of W/O/W DEs could be regulated by perfusion fluid flow rates. These features endow this platform with potential to continuously supply encapsulated non-adherent cells with nutrients or small-molecule stimuli/drugs through fluid perfusion. Meanwhile, the confinement of cells in the anchored DEs favored long-term monitoring of cellular dynamic behaviors and responses. As a proof of concept, fluorescein diacetate (FDA) was employed to visualize the cellular uptake and biochemical metabolism of TF-1 human erythroleukemia cells. We believe that this W/O/W DE anchorage and perfusion platform would benefit single-cell-level studies as well as small-molecule drug discovery requiring live non-adherent cells. [ABSTRACT FROM AUTHOR]