Investigation of H-bonding of p-(3-carboxymethyl-1-adamantyl)calix[6]arene by IR spectroscopy

Synthesis of glucosamine-selenium compound and evaluation of its oral toxicity and in vitro anti-hepatitis B virus activity

Selenium supplements are beneficial to human health, however, concerns regarding the toxicity of inorganic selenium have stimulated research on safer organic compounds. The main objective of this study was to develop a novel glucosamine-selenium compound (Se-GlcN), clarify its structure, and subsequently investigate its oral toxicity and in vitro anti-hepatitis B virus (HBV) activity. Electron microscopy, infrared, ultraviolet spectroscopy, nuclear magnetic resonance and thermogravimetric analyses revealed a unique binding mode of Se-GlcN, with the introduction of the Se-O bond at the C6 position, resulting in the formation of two carboxyl groups. In acute toxicity studies, the median lethal dose (LD50) of Se-GlcN in ICR mice was 92.31 mg/kg body weight (BW), with a 95 % confidence interval of 81.88-104.07 mg/kg BW. A 30-day subchronic toxicity study showed that 46.16 mg/kg BW Se-GlcN caused livers and kidneys damage in mice, whereas doses of 9.23 mg/kg BW and lower were safe for the livers and kidneys. In vitro studies, Se-GlcN at 1.25 μg/mL exhibited good anti-HBV activity, significantly reducing HBsAg, HBeAg, 3.5 kb HBV RNA and total HBV RNA by 45 %, 54 %, 84 %, 87 %, respectively. In conclusion, the Se-GlcN synthesized in this study provides potential possibilities and theoretical references for its use as an organic selenium supplement.

Co-construction of molecular-level uranyl-specific "nano-holes" with amidoxime and amino groups on natural bamboo strips for specifically capturing uranium from seawater

Efficiently capturing of uranium (VI) [U(VI)] from seawater elicits unparalleled attraction for sustaining the uplifted requirement for nuclear fuel. However, obtaining the abundant U(VI) resource from seawater has always seriously restricted by competitive adsorption from higher concentrations of competitors, especially vanadium (V) [V(V)]. Herein, based on amidoximized natural bamboo strips with hierarchical porous structure, the molecular-level uranyl-specific "nano-holes" was co-constructed by the intramolecular hydrogen bonds for specifically trapping U(VI) from seawater. Manipulating the branched degrees of amino groups enabled the creation of a series of the molecular-level uranyl-specific "nano-holes" that exhibit ultrahigh affinity and selective adsorption of U(VI) with a adsorption capacity 1.8 fold higher compared to that of V(V) after 30 days floating in the Yellow Sea basin, conquering the long-term challenge of the competitive adsorption of V(V) for amidoxime-based adsorbents applied to extract U(VI) from seawater. The diameter of the molecular-level uranyl-specific "nano-holes" is approximately 12.07 Å, significantly larger than (UO₂)₃(OH)₃⁺ (10.37 Å) and smaller than HV₁₀O₂₈^5-, thereby exhibiting specifically trapping of U(VI) in a series of adsorption experiments with different U(VI)-V(V) ratios. Besides, the adsorption model based on the combination of experimental and theoretical results is accompanied by "hydrogen bond breaking and coordination bond formation".