A nanoparticle-based drug delivery system is first established by mesoporous silica encapsulating amino acid–intercalated layered double hydroxide (LDH) to construct nanocomposites AA-LDH@MS. The amino acids including phenylalanine (Phe) and histidine (His) with aromatic groups are intercalated into LDH as the cores Phe-LDH and His-LDH. These nanocomposites AA-LDH@MS display multispaces of the interlayer spaces of LDH and porous channels of mesoporous silica to load drugs. Moreover, amino acid molecules provide the interaction sites to improve effectively loading amounts of drugs. 5-Fluorouracil (5-FU) is used as the cargo molecules to observe the delivery in vitro. The results indicate that the maximum loading amounts of drugs are up to 392 mg/g at 60 °C for 12 h in the nanocomposite Phe-LDH@MS. All the nanocomposites exhibit the sustained release of 5-FU at pH 4 and pH 7.4. The Korsmeyer–Peppas model is used to fit the kinetic plot of the drug release in vitro, which concludes that 5-FU release from AA-LDH@MS belongs to Fickian diffusion.

Three-dimensional (3D) bioprinting has become a fast-developing research field in the last few years. Many different technical solutions are available, with extrusion-based printing being the most promising and versatile method. In addition, a variety of biomaterials are already available for 3D printing of live cells. The real challenge, however, remains bioprinting of macroscopic, volumetric constructs of well-defined structures since hydrogels used for cell-embedding must consist of rather soft materials. This article describes recent developments to overcome these limitations that prevent clinical applications of bioprinted human tissues. New approaches include technical solutions such as in situ cross-linking or gelation processes that now can be performed during the bioprinting process, modified bioinks that combine suitable viscosity and cytocompatible gelation mechanisms, and utilization of additional materials to provide mechanical strength to the cell-laden constructs.

The spectrally and temporally resolved luminescence of three-dimensional (3D) InGaN/GaN microrods and planar light emitting diode (LED) structures is studied for different energy densities of fs-laser excitation pulses and for different sample temperatures. We find an energy density threshold above which irreversible modifications of the structures take place, which leads to a decrease of the luminescence intensity and a change in the intensity ratio of the GaN to the InGaN luminescence. Due to the quantum confined Stark effect, a biexponential decay characteristic is found in the planar structure, while the 3D microrods with nonpolar InGaN quantum wells on their sidewalls show a monoexponential decay of the InGaN luminescence. For both structures, the decay of the luminescence becomes faster with increasing energy density per pulse. However, the luminescence of the planar LED decays faster with increasing temperature, while the opposite trend is found for the 3D sample.

Zeolite–zeolite composite composed of alumina-rich hierarchically porous ZSM-5 cores and high-silicon MFI shells was prepared by a hydrothermal synthesis procedure, in which a commercial ZSM-5 zeolite with a SiO2/Al2O3 of 36 was treated by an alkaline solution and then used as a supporter for epitaxial growth of a polycrystalline Silicalite-1 zeolite shell (denoted as MMZsa). Acid sites associated with framework Al on exterior surfaces of ZSM-5 zeolite cores are therefore passivated in different degrees by the epitaxial MFI zeolite shell. The structural, crystalline, and textural properties of the as-synthesized samples were characterized by x-ray powder diffraction (XRD), energy-dispersive x-ray spectroscopy, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), N2 adsorption-desorption, in situ IR spectra of pyridine and NH3-TPD. Aluminum species were observed to transfer from the alumina-rich cores to the high-silica shells. The adjustable thickness and SiO2/Al2O3 ratio of the shell offer the as-synthesized composite a potential and high-efficiency catalyst for methanol conversion into gasoline and diesel. As compared with the commercial ZSM-5 zeolite, the composite catalyst exhibits excellent catalytic performances with a longer catalytic life as well as a higher conversion and a slightly higher yield of diesel oil.

A novel core–shell particle that consists of epoxide-terminated hyperbranched polymer (HBP) and silica nanoparticles was incorporated into an epoxy/hydroxyl-terminated HBP blend to fabricate a high-performance epoxy thermoset. The effect of the core–shell particle content on the mechanical properties of the epoxy thermosets was investigated in detail. Results from tensile, flexural, and impact tests are provided. The impact fracture surface was studied by field emission-scanning electron microscopy. The incorporation of 2 wt% core–shell particles improved the tensile strength, percent elongation at break, flexural strength, and impact resistance of epoxy/hydroxyl-terminated HBP thermosets. Field emission-scanning electron micrographs showed that core–shell particle addition resulted in large-scale shear deformation and debonding from the epoxy matrix, and improved the epoxy resin toughness.