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With the increase concern of solubilization for insoluble drug, ternary solid dispersion (SD) formulations developed more rapidly than binary systems. However, rational formulation design of ternary systems and their dissolution molecular mechanism were still under development. Current research aimed to develop the effective ternary formulations and investigate their molecular mechanism by integrated experimental and modeling techniques. Glipizide (GLI) was selected as the model drug and PEG was used as the solubilizing polymer, while surfactants (e.g., SDS or Tween80) were the third components. SD samples were prepared at different weight ratio by melting method. In the dissolution tests, the solubilization effect of ternary system with very small amount of surfactant (drug/PEG/surfactant 1/1/0.02) was similar with that of binary systems with high polymer ratios (drug/PEG 1/3 and 1/9). The molecular structure of ternary systems was characterized by differential scanning calorimetry (DSC), infrared absorption spectroscopy (IR), X-ray diffraction (XRD), and scanning electron microscope (SEM). Moreover, molecular dynamic (MD) simulations mimicked the preparation process of SDs, and molecular motion in solvent revealed the dissolution mechanism of SD. As the Gordon-Taylor equation described, the experimental and calculated values of Tg were compared for ternary and binary systems, which confirmed good miscibility of GLI with other components. In summary, ternary SD systems could significantly decrease the usage of polymers than binary system. Molecular mechanism of dissolution for both binary and ternary solid dispersions was revealed by combined experiments and molecular modeling techniques. Our research provides a novel pathway for the further research of ternary solid dispersion formulations.

Carbon-based materials are widely used for environmental remediation because of their unique and excellent performances. Because of the huge daily consumption of such materials, the economic and environmental friendly derivations from natural biomass are highly desired. Herein, a new biocarbon composite, carbonized loofah/tin­(IV) sulfide (CLF@SnS2) foam, was successfully prepared using loofah biofoam through an efficient and scalable method. The hierarchical CLF@SnS2 foam has a high-porous structure, which can provide channels for light traveling through the whole material. It is confirmed that such three-dimensional photocatalytic material can quickly purify Cr­(VI)-containing wastewater under mild visible light irradiation, with a efficiency of 99.7% Cr­(VI) reduction within 120 min. By contrast, CLF@SnS2 showed much better visible photocatalytic capacity than the uncarbonized counterpart (UCLF@SnS2), because the photoelectrons produced by the SnS2 nanosheets can be rapidly exported by the continuous channels provided by the carbon shell. Besides the high visible light-driven photocatalytic activity, CLF@SnS2 also exhibits excellent cycling stability. More importantly, this study demonstrated that CLF@SnS2 can be used for practical applications due to its flexibility and economic availability.

A single crystal of 2D layered α‐MoO2 using a simple technique of physical vapor deposition (PVD) method is generated. By adjusting the growth temperature, the thickness of α‐MoO2 single crystals can be tuned to sub ten nanometers. High‐resolution transmission electron microscopy (HRTEM) images verified the atomic structural details of PVD grown orthorhombic MoO2 (α‐MoO2) nanosheet with high quality. Additionally, the unsaturated linear magnetic range (LMR) in the grown nanosheets is up to 5 T. Also, α‐MoO2 nanosheet with low defect displays excellent conductivity that is comparable to the metal silver. Thus, this new nanomaterial can show a promising application as a potential 2D conductor.