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Phosvitin phosphopeptides (PPP) have a high ability to chelate mineral ions and promote calcium absorption. In this study, The Fe 3 O 4 nanospheres were first synthesized by hydrothermal method, then the three magnetic nanoparticles (Fe 3 O 4 @PDA@PMAA@PAMAM, Fe 3 O 4 @PDA@Ce4+, and Fe 3 O 4 @PDA@TiO 2) were obtained by layer modification on their surfaces, respectively. The magnetic nanoparticles were characterized by TEM, XRD, VSM, and Zeta potential. TEM analysis revealed that the nanoparticles were spherical and regular in shape. XRD diffraction analysis showed that the modified nanoparticles have a complete crystal structure. Meanwhile, PAMAM, Ce4+, TiO 2 , and other groups have been successfully modified on the nanoparticles. VSM hysteresis regression line results revealed that the magnetic nanoparticles are superparamagnetic. The three kinds of magnetic nanoparticles still maintained excellent enrichment performance after five times of repeated use. Fe 3 O 4 @PDA@TiO 2 has the best enrichment performance (167 mg g−1). The N/P ratio of the enriched PPP decreased from 1.36 to 0.98, which also showed that it had excellent PPP enrichment performance. Therefore, the modified magnetic nanoparticles could be an optimal PPP enrichment and purification material. [Display omitted] • Fe 3 O 4 magnetic nanoparticles were synthesized and characterized. • The modified magnetic nanoparticles have good stability, dispersion and repeatability. • The nanoparticles were effectively applied for the enrichment of phosvitin phosphopeptides. [ABSTRACT FROM AUTHOR]

Abstract: We developed solid dispersions, using the gas anti-solvent technique (GAS), to improve the oral bioavailability of the poorly water-soluble active component oridonin. The solubility of oridonin in supercritical carbon dioxide was measured under various pressures and temperatures. To prepare oridonin solid dispersions using the GAS technique, ethanol was used as the solvent, CO2 was used as the anti-solvent and the hydrophilic polymer polyvinylpyrrolidone K17 (PVP K17) was used as the drug carrier matrix. Characterization of the obtained preparations was undertaken using scanning electron microscopy (SEM), X-ray diffraction (XRD) analyses and a drug release study. Oridonin solid dispersions were formed and oridonin was present in an amorphous form in these dispersions. Oridonin solid dispersions significantly increased the drug dissolution rate compared with that of oridonin powder, primarily through drug amorphization. Compared with the physical mixture of oridonin and PVP K17, oridonin solid dispersions gave higher values of AUC and C max, and the absorption of oridonin from solid dispersions resulted in 26.4-fold improvement in bioavailability. The present study illustrated the feasibility of applying the GAS technique to prepare oridonin solid dispersions, and of using them for the delivery of oridonin via the oral route. [Copyright &y& Elsevier]

Green hydrogen is a clean energy, and its application scenarios have become increasingly diverse with the development of hydrogen energy equipment. To ensure the safe use of hydrogen, it is essential to study the leakage and dispersion characteristics of hydrogen in different spaces. In this work, the experimental and numerical simulation studies on hydrogen leakage and dispersion were conducted in spaces with large aspect ratios. The research found that hydrogen leakage and dispersion can be divided into three typical stages: buoyancy-dominated stage, horizontal spreading stage, and vertical filling stage. The relationship between the concentration rise rate of hydrogen and the leakage rate and leakage direction in the third stage is established. As the leakage speed increases, the dispersion time of hydrogen decreases, leading to significant differences in concentration distribution. Changes in the leakage direction will influence the interaction between hydrogen and the walls, subsequently altering the dispersion behavior of hydrogen. Changes in leakage speed and direction do not affect the sequence of hydrogen dispersion to specific points in space. Based on the characteristics of hydrogen dispersion, a subjective-objective integrated hydrogen weighted concentration calculation method was proposed in this study. The hydrogen weighted concentration can be effectively characterized the leakage and dispersion characteristics of hydrogen. The value always approaches 50% of the average concentration, which can be used for determining the warning threshold or specifying emergency strategies. • The hydrogen dispersion process consists of three stages in large aspect ratio space. • The hydrogen dispersion sequence to a point unaffected by leakage rate and direction. • The hydrogen concentration rise rate model during linear rise is given. • A subjective-objective combined weighted concentration calculation method is given. [ABSTRACT FROM AUTHOR]