Amorphous calcium phosphate (ACP) has shown significant effects on the biomineralization and promising applications in bio-medicine. However, the limited stability and porosity of ACP material restrict its practical applications. A storage stable highly porous ACP with Brunauer–Emmett–Teller surface area of over 400 m2/g was synthesized by introducing phosphoric acid to a methanol suspension containing amorphous calcium carbonate nanoparticles. Electron microscopy revealed that the porous ACP was constructed with aggregated ACP nanoparticles with dimensions of several nanometers. Large angle X-ray scattering revealed a short-range atomic order of <20 Å in the ACP nanoparticles. The synthesized ACP demonstrated long-term stability and did not crystallize even after storage for over 14 months in air. The stability of the ACP in water and an α-MEM cell culture medium were also examined. The stability of ACP could be tuned by adjusting its chemical composition. The ACP synthesized in this work was cytocompatible and acted as drug carriers for the bisphosphonate drug alendronate (AL) in vitro. AL-loaded ACP released ~25% of the loaded AL in the first 22 days. These properties make ACP a promising candidate material for potential application in biomedical fields such as drug delivery and bone healing.

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Fused deposition modelling (FDM) is the most extensively employed 3D-printing technique used in pharmaceutical applications, and offers fast and facile formulation development of personalized dosage forms. In the present study, mesoporous materials were incorporated into a thermoplastic filament produced via hot-melt extrusion and used to produce oral dosage forms via FDM. Mesoporous materials are known to be highly effective for the amorphization and stabilization of poorly soluble drugs, and were therefore studied in order to determine their ability to enhance the drug-release properties in 3D-printed tablets. Celecoxib was selected as the model poorly soluble drug, and was loaded into mesoporous silica (MCM-41) or mesoporous magnesium carbonate. In vitro drug release tests showed that the printed tablets produced up to 3.6 and 1.5 times higher drug concentrations, and up to 4.4 and 1.9 times higher release percentages, compared to the crystalline drug or the corresponding plain drug-loaded mesoporous materials, respectively. This novel approach utilizing drug-loaded mesoporous materials in a printed tablet via FDM shows great promise in achieving personalized oral dosage forms for poorly soluble drugs.

Highly porous amorphous mesoporous magnesium carbonate (MMC) with a Brunauer–Emmett–Teller (BET) surface area over 600 m2·g–1 was evaluated as a micrometer-sized support for TiO2 and ZnO semiconductor nanoparticles. The resulting MMC-TiO2-ZnO contained 25 wt % TiO2 and 25 wt % ZnO incorporated into an MMC structure without blocking the pores as revealed by nitrogen sorption isotherms, scanning electron microscopy, and transmission electron microscopy. In vitro ultraviolet (UV) light-blocking experiments showed that the MMC-TiO2-ZnO had comparable UV-blocking ability as a TiO2 and ZnO nanoparticle mixture containing the same amount of semiconductor particles without a support. Amaranth dye degradation studies revealed that MMC was able to diminish the catalytic activity of TiO2 and ZnO nanoparticles, possibly due to the presence of free carbonate ions in MMC as well as in the dye solution. In summary, this paper demonstrated for the first time that micrometer-sized particles of the recently emerged MMC materials can be used as a support for sun-blocking semiconductor nanoparticles without compromising their UV blocking ability and with significantly lowered photocatalytic activity. When used in a formulation as a support for semiconductor nanoparticles, MMC may also reduce the risk of nanoparticle exposure, and the high porosity of MMC-TiO2-ZnO may be utilized for the delivery of therapeutic agents to the skin.

A metal−organic framework (MOF) CTH-17 based on lanthanum-(III) and the conformationally chiral linker 1,2,3,4,5,6-hexakis(4-carboxyphenyl)benzene, cpb 6− : [La 2 (cpb)]•1.5dmf was prepared by the solvothermal method in dimethylformamide (dmf) and characterized by variable-temperature X-ray powder diffraction (VTPXRD), variable-temperature X-ray single-crystal diffraction (SCXRD), and thermogravimetric analysis (TGA). CTH-17 is a rod-MOF with new topology och. It has high-temperature stability with Sohncke space groups P6 1 22/P6 5 22 at 90 K and P622 at 300 and 500 K, all phases characterized with SCXRD and at 293 K also with three-dimensional (3D) electron diffraction. VTPXRD indicates a third phase appearing after 620 K and stable up to 770 K. Gas sorption isotherms with N 2 indicate a modest surface area of 231 m 2 g −1 for CTH-17, roughly in agreement with the crystal structure. Carbon dioxide sorption reveals a gate-opening effect of CTH-17 where the structure opens up when the loading of CO 2 reaches approximately ∼0.45 mmol g −1 or 1 molecule per unit cell. Based on the SCXRD data, this is interpreted as flexibility based on the concerted movements of the propeller-like hexatopic cpb linkers, the movement intramolecularly transmitted by the π−π stacking of the cpb linkers and helped by the fluidity of the LaO 6 coordination sphere. This was corroborated by density functional theory (DFT) calculations yielding the chiral phase (P622) as the energy minimum and a completely racemic phase (P6/mmm), with symmetric cpb linkers representing a saddle point in a racemization process.