Release Mechanisms and Practical Percolation Threshold for Long-acting Biodegradable Implants: An Image to Simulation Study

Microstructure Formation and Characterization of Long-Acting Injectable Microspheres: The Gateway to Fully Controlled Drug Release Pattern

“…97 The ion beam generated by the ion source is accelerated by the ion gun and acts on the sample surface, while the atoms on the surface are stripped by the ion beam with strong current to achieve the nano surface topography processing without disrupting microspheres in the next layer. 29,85 Compared with mechanically-cut microspheres, FIB can provide higher accuracy and precision, thus obtaining a clean and artifact-free cross section for high-resolution SEM imaging. 8,98 For subsequent SEM imaging, the beam emitted by the electron gun passes through a pair of objective lens and aperture to form an extremely narrow high-energy electron beam, which is further focused on the sample surface through objective lens.…”

“…The high-resolution FIB-SEM can capture more details of the target sample. 85 Clark et al 8 prepared eight microspheres with different microstructures by changing the formulation and processing procedure. 2D FIB-SEM imaging and 3D tomography microsphere reconstruction were conducted to fully quantify microstructures, which including API and pore fractions, size distribution and spatial distribution, and eventually used for the prediction of drug release.…”