Search

In this paper, we reported a facile approach for the preparation of sulfur and nitrogen co-doped carbon nanoparticles (S,N-CNPs) with strong blue luminescence, which exhibited multiple applications including metal ion detection, logic gate fabrication and bioimaging. S,N-CNPs were synthesized by one-step hydrothermal treatment of formamidine sulfinic acid (FAS) and ethylene glycol. The as-synthesized S,N-CNPs possess a high quantum yield (Φ = 69.04%) and display excellent photostability and storage stability. By modulating the pH environment, S,N-CNPs were successfully applied as fluorescent probes for the detection of three kinds of heavy metal ions (Hg2+, Ag+ and Ni2+). The fabricated fluorescence sensors display ultrahigh sensitivity and a wider signal response range. More importantly, ethylenediamine (or ammonium thioglycolate and glycine) could efficiently release Hg2+ (or Ag+ and Ni2+) from the S,N-CNP surface, leading to the recovery of the fluorescence. According to this phenomenon, interesting implication (IMP) logic gates were constructed. In addition, the S,N-CNPs exhibited low toxicity, good biocompatibility and easy cellular uptake behavior. Consequently, the obtained S,N-CNPs will have potential applications in multiple fields of environmental monitoring, logic gate operation, and cell bioimaging. [ABSTRACT FROM AUTHOR]

Three-dimensional δ-MnO2-cladded CuCo2O4 composites are designed and grown in situ on Ni foam via a simple hydrothermal reaction and subsequent one-pot chelation-mediated aqueous processes. The electrode architecture can take good advantage of the synergistic effects contributed by both the porous CuCo2O4 nanoflake core and the δ-MnO2 shell layer. When δ-MnO2-cladded CuCo2O4 composites, along with porous Ni foam, are employed as a binder-free electrode for supercapacitors, the hybrid electrode shows higher specific capacitances and a better rate capability than the single CuCo2O4 nanoflake electrode. A maximum specific capacitance of 1180 F g−1 is achieved at a current density of 1 A g−1 and 81.7% of this value remains at a high current density of 10 A g−1. Moreover, the δ-MnO2-cladded CuCo2O4 electrode also delivers an excellent cycling stability, maintaining 93.2% at 15 A g−1 after 5000 galvanostatic charge–discharge cycles. Moreover, according to electrochemical impedance spectroscopy (EIS) analysis, the δ-MnO2-cladded CuCo2O4 electrode possesses a lower equivalent series resistance of 0.78 Ω and a charge transfer resistance of 0.09 Ω. In view of its cost-effective fabrication process and excellent energy storage properties, this unique integrated nanoarchitecture would hold great promise in the field of electrochemical energy storage. [ABSTRACT FROM AUTHOR]

In this research a method called immobilized cell capillary electrophoresis (ICCE) was established under approximately physiological conditions for rapid screening of anti-tumor metastasis drugs targeting integrin macrophage antigen-1 (MAC-1). In this method, separation and purification of the target receptors on cell membranes was unnecessary, thus, maintaining their natural conformation and bioactivity. MAC-1-, CD11b-, or CD18-overexpressing HEK293 cells (human embryonic kidney) were cultured and immobilized on the inner wall of capillaries as stationary phase, and their interactions with lactosyl derivative Gu-4 (positive control)/dimethylsulfoxide (DMSO; negative control) were studied using ICCE. Using this method, 29 phenylethanoid glycosides from Cistanches Herba were screened, and the binding kinetic parameters (K, ka, kd, and k′) of active compounds were calculated, and the specific subunits of MAC-1 were determined. Then, molecular docking studies were performed to discover the direct interaction sites between active compounds and MAC-1, and the order of Glide-calculated Emodel value obtained from the molecular docking study is consistent with that of the binding constants obtained using ICCE. Finally, pharmaceutical efficacy assays in vitro and in vivo were carried out to show that the anti-tumor metastasis activity of the active compound had better pharmaceutical efficacy and lower toxic side effects. The method was verified to be valid and practical for further use, and it is expected that it will be transferred to capillary array electrophoresis for use in high-throughput drug screening. [ABSTRACT FROM AUTHOR]

In this work, MoO3 microsheets were successfully prepared by thermally oxidizing the MoO2 nanospheres synthesized by a hydrothermal method. The crystal structures and morphologies of precursor MoO2 and the final product were characterized by XRD, FESEM, and TEM. Gas sensors based on MoO3 were fabricated and their gas sensing properties were tested. These results revealed that they exhibited excellent sensing performance towards triethylamine (TEA) with high selectivity, good repeatability, relatively high response and short response time (＜3 s). In particular, the fabricated sensor displayed excellent long-term stability and superior selectivity, making it a promising triethylamine gas sensor. The possible reasons related to these characteristics of MoO3 microsheets are further discussed. [ABSTRACT FROM AUTHOR]

Here we found that the enantioselectivity of G-quadruplex DNA-based Diels–Alder reaction can be switched by just changing Na+ to K+, which is ascribed to the structural transformation of the G-quadruplex from antiparallel to hybrid-type. By tuning the ratio of Na+/K+, the enantioselectivity of the Diels–Alder reaction could be switchable and shows much more sensitive to K+ than to Na+. [ABSTRACT FROM AUTHOR]

Here we found that the enantioselectivity of G-quadruplex DNA-based Diels-Alder reaction can be switched by just changing Na(+) to K(+), which is ascribed to the structural transformation of the G-quadruplex from antiparallel to hybrid-type. By tuning the ratio of Na(+)/K(+), the enantioselectivity of the Diels-Alder reaction could be switchable and shows much more sensitive to K(+) than to Na(+).