Preparation and Characterization of Lutein Co-Amorphous Formulation with Enhanced Solubility and Dissolution.

Lutein is an oxygenated fat-soluble carotenoid and a functional compound with proven health benefits for the human body. Nevertheless, the poor water solubility and low oral bioavailability of lutein greatly limit its application. To address this, we developed an effective approach to enhance the water solubility of lutein through co-amorphous formulation. Specifically, the lutein-sucralose co-amorphous mixture was prepared at a molar ratio of 1:1 using ethanol and water as solvents by employing the solvent evaporation method, followed by solid-state characterization and dissolution testing conducted to assess the properties of the formulation. The X-ray diffraction pattern with an amorphous halo and the differential scanning calorimetry thermogram with no sharp melting peaks confirmed the formation of a binary co-amorphous system. Changes in peak shape, position, and intensity observed in the Fourier transform infrared spectroscopy spectrum revealed intermolecular interactions between lutein and sucralose molecules, while molecular dynamics simulations identified interaction sites between their hydroxyl groups. Additionally, dissolution testing demonstrated better dissolution performance of lutein in the co-amorphous form compared to pure lutein and physical mixture counterparts. Our findings present a novel strategy for improving the water solubility of lutein to make better use of it.

Anaerobic granular sludge performance in an expanded granular sludge bed reactor treating calcium-rich wastewater by adjusting CaCO3 crystallization: Effect of upflow velocity and Ca2+ concentration.

The role of upflow velocity and Ca2+ concentration in controlling the type and rate of CaCO3 crystallization and their impacts on the anaerobic granular sludge (AnGS) formation and performance in an expanded granular sludge bed (EGSB) reactor were studied. The results showed that an improved upflow velocity could promote metastable CaCO3 crystals and achieve the optimized portion of vaterite with a value of 84 % at 10 m/h with a small amount of aragonite, thus limiting the scaling in the reactor. The removal efficiency of Ca2+ was to some extent positively correlated to the influent Ca2+ concentration, but declined when Ca2+ exceeded a specific threshold. Vaterite was dominant with the increase of Ca2+ concentrations of the influent. Compared with granules in R1 (Ca2+ 10 mg/L) and R2 (Ca2+ 100 mg/L), granules cultivated in R3 (Ca2+ 800 mg/L) revealed maximum amount of biomass with biggest particle size distribution and fastest average settling rate, with relative stable COD removal efficiency and the fast optimized reactor capacity at OLR of 16 kgCOD/m3d. A low upflow velocity and a higher Ca2+ concentration promoted nucleus formation and granules growth at the initial cultivation stage of the EGSB reactor. The Ca2+ concentration had a significant impact on the bacterial community and favoured the growth of Tolumonas and Anaeromousa Anaeroarcus. Archaea, rather than bacteria, was strengthened to contribute more to methane production at a relatively high Ca2+ concentration.

Mo2C Nanoparticles Dispersed on Hierarchical Carbon Microflowers for Efficient Electrocatalytic Hydrogen Evolution.

The development of nonprecious metal based electrocatalysts for hydrogen evolution reaction (HER) has received increasing attention over recent years. Previous studies have established Mo2C as a promising candidate. Nevertheless, its preparation requires high reaction temperature, which more than often causes particle sintering and results in low surface areas. In this study, we show supporting Mo2C nanoparticles on the three-dimensional scaffold as a possible solution to this challenge and develop a facile two-step preparation method for ∼3 nm Mo2C nanoparticles uniformly dispersed on carbon microflowers (Mo2C/NCF) via the self-polymerization of dopamine. The resulting hybrid material possesses large surface areas and a fully open and accessible structure with hierarchical order at different levels. MoO42- was found to play an important role in inducing the formation of this morphology presumably via its strong chelating interaction with the catechol groups of dopamine. Our electrochemical evaluation demonstrates that Mo2C/NCF exhibits excellent HER electrocatalytic performance with low onset overpotentials, small Tafel slopes, and excellent cycling stability in both acidic and alkaline solutions.