TOWARD CONTROLLED-RELEASE DRUG DELIVERY MICROCARRIERS ENABLED BY DIRECT LASER WRITING 3D PRINTING.

Controlled-release, and especially long-acting, drug delivery systems hold promise for improving treatments for numerous medical conditions. Previously, we reported an additive manufacturing or "three-dimensional (3D) printing" approach for fabricating liquid-core-shell-cap microcarriers comprising standard photoresists. Here we explore the potential to extend this strategy to achieve microcarriers comprising biodegradable materials as a new pathway to controlled-release drug delivery options.

Quantitative order-parameter measurement in lattice-mismatched AlInP using precession electron diffraction.

Precession electron diffraction (PED) was used to measure the long-range order parameter in lattice-mismatched AlInP epitaxial films under investigation for solid-state-lighting applications. Both double- and single-variant films grown at 620, 650 and 680 °C were analysed in TEM cross-section. PED patterns were acquired in selected-area-diffraction mode through external microscope control using serial acquisition, which allows inline image processing.

Annealing-induced precipitate formation behavior in MOVPE-grown GaAs Bi explored by atom probe tomography and HAADF-STEM.

The effects of a 45 min anneal at 800 °C on the physical properties and microstructure of a five-period GaAs Bi /GaAs Bi superlattice with y ≠ x were studied using room-temperature photoluminesence spectroscopy, high-resolution x-ray diffraction, high-angle annular-dark-field scanning transmission electron microscopy (HAADF-STEM), and atom probe tomography (APT). The anneal resulted in a substantial increase of the photoluminesence intensity over that observed in the as-deposited sample, indicating annihilation of non-radiative recombination centers and stability of the superlattice structure during the anneal. However, some precipitation of Bi from the GaAs Bi also occurred.