Applicability of Raman and near-infrared spectroscopy in the monitoring of freeze-drying injectable ibuprofen.

The freeze-drying process is an expensive, time-consuming and rather complex process. Therefore, process analytical technology (PAT) tools have been introduced to develop an optimized process and control critical process parameters, which affect the final product quality. The aim of the present work was to study the applicability of at-line near-infrared (NIR) and Raman spectroscopy approach in the monitoring of the freeze-drying process.

Silicon surface deoxidation using strontium oxide deposited with the pulsed laser deposition technique.

The epitaxial growth of functional oxides on silicon substrates requires atomically defined surfaces, which are most effectively prepared using Sr-induced deoxidation. The manipulation of metallic Sr is nevertheless very delicate and requires alternative buffer materials. In the present study the applicability of the chemically much more stable SrO in the process of native-oxide removal and silicon-surface stabilization was investigated using the pulsed-laser deposition technique (PLD), while the as-derived surfaces were analyzed in situ using reflection high-energy electron diffraction and ex situ using X-ray photoelectron spectroscopy, X-ray reflectivity, and atomic force microscopy.