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The Ca–Al oxide catalysts are prepared via thermal decomposition of Ca–Al layered double hydroxide precursors and characterized by XRD, TG, SEM, BET, CO2-TPD, Hammett indicators, XPS and ICP techniques. The obtained catalysts are then tested for transesterification of methanol with propylene carbonate (PC), highest dimethyl carbonate (DMC) yield of 59.9% has been reached with methanol: PC molar ratio of 12, catalysts weight of 2 wt% total reactants, and reaction time of 2 h. Research results show that though the transesterification occurs over various basic sites, the strong basic site has a leading role on transesterification, which is consistent with the activity results. The catalysts can be recycled and the reason for the decrease in catalytic activity is further discussed in detail. The catalytic performance of Ca-Al solid base catalysts derived from Ca-Al layered double hydroxides for dimethyl carbonate production under heterogeneous conditions.

The Ca–Al and Ca–Al–X (X = F−, Cl− and Br−) catalysts were prepared via thermal decomposition of Ca–Al layered double hydroxides (LDHs), and tested for methanolysis of propylene carbonate (PC) to produce dimethyl carbonate (DMC). The catalytic performance of these catalysts increased in the order of Ca–Al–Br− < Ca–Al < Ca–Al–Cl− < Ca–Al–F−, which was consistent with the strong basicity of these materials. The recyclability test results showed that the addition of Al and halogens (F−, Cl− and Br−) not only stabilized the CaO but also improved the recyclability of the catalysts. Particularly, the Ca–Al–F− catalyst exerted the highest stability after 10 recycles. These catalysts have an important value for the exploitation of DMC synthesis by transesterification of PC with methanol.

Composite solid base catalysts derived from Ca-M-Al (M = Mg, La, Ce, Y) layered double hydroxides (LDH) were synthesized, characterized and applied to the transesterification of methanol with propylene carbonate. X-ray diffraction analyses of the catalysts show that all of the catalysts were in the form of composite oxides. Compared with the Ca-Al LDH catalyst, the specific surface areas and pore volumes of the catalysts were increased with the introduction of Mg, La or Ce. The catalytic performance of these catalysts increases in the order of Ca-Y-Al

Because of the peculiarity of the bone microstructure, the uptake of chemotherapeutics often happens at non-targeted sites, which induces side effects. In order to solve this problem, we designed a bone-targeting drug delivery system that can release drug exclusively in the nidus of the bone. Alendronate (ALN), which has a high ability to target to hydroxyapatite, was used to fabricate double ALN-conjugated poly (ethylene glycol) 2000 material (ALN-PEG2k-ALN). The ALN-PEG2k-ALN was characterized using 1H NMR and 31P NMR and FTIR. ALN-PEG2k-ALN-modified calcium phosphate nanoparticles (APA-CPNPs) with an ALN targeting moiety and hydrophilic poly (ethylene glycol) arms tiled on the surface was prepared for bone-targeted drug delivery. The distribution of ALN-PEG2k-ALN was tested by X-ray photoelectron spectroscopy. Isothermal titration calorimetry data indicated that similar to free ALN, both ALN-PEG2k-ALN and APA-CPNPs can bind to calcium ions. The bone-binding ability of APA-CPNPs was verified via ex vivo imaging of bone fragments. An in vitro release experiment demonstrated that APA-CPNPs can release drug faster in an acid environment than a neutral environment. Cell viability experiments indicated that blank APA-CPNPs possessed excellent biocompatibility with normal cells. Methotrexate (MTX) loaded APA-CPNPs have the same ability to inhibit cancer cells as free drug at high concentrations, while they are slightly weaker at low concentrations. All of these experiments verified the prospective application of APA-CPNPs as a bone-targeting drug delivery system.

Agomelatine (AGM), is efficacious in both the acute phase and the continuation phase of depression. However, its poor water-solubility, low bioavailability and polymorphism limit its pharmacological effects. To address these problems, agomelatine-hydroxypropyl-β-cyclodextrin inclusion complex (AGM/HPβ-CD) was prepared successfully by freeze-drying. The products was evaluated by structural characterization, solubilization test, in-situ absorption of rat intestinal tract and pharmacokinetic study. In addition, thermodynamic studies were performed, the results indicated that the inclusion process was enthalpy-determined and exothermic nature of complexation, signifying the role of steric interactions in complex formation. Molecular docking of AGM with HPβ-CD has been conducted as well to verify the experimental findings and predict the stable molecular structure of the inclusion complex. The in vivo data showed that, AGM was mainly absorbed in duodenum and jejunum by passive diffusion. AGM/HPβ-CD inclusion complex displayed earlier Tmax and higher Cmax, and the AUC0-12h was approximately twice larger than its physical mixture. These results suggested that AGM/HPβ-CD inclusion complex was established with 1:1 stoichiometry through the naphthalene group of AGM and it was deeply inserted into the cavity of HPβ-CD, and the inclusion complex could significantly enhance the oral bioavailability of AGM.

The aim of the present study was to develop layered double hydroxide (LDH) nanoparticles coated with PEGylated phospholipid membrane. By comparing the size distribution and zeta potential, the weight ratio of LDH to lipid materials which constitute the outside membrane was identified as 2:1. Transmission electron microscopy photographs confirmed the core-shell structure of PEGylated phospholipid membrane coated LDH (PEG-PLDH) nanoparticles, and cell cytotoxicity assay showed their good cell viability on Hela and BALB/C-3T3 cells over the concentration range from 0.5 to 50 μg/mL.