UV-VIS spectra as potential process analytical technology (PAT) for measuring the density of compressed materials: Evaluation of the CIELAB color space.

Measurement methods for determining the density of compressed materials, being a critical quality attribute, provide an important parameter for successful processing. In this study, a novel approach was developed for determining the density of compacts using ultraviolet-visible spectrophotometry. The assumption within this context was that a change in density affects the corresponding color information of the compact.

Raman Imaging of Plant Cell Walls in Sections of Cucumis sativus.

Raman microspectra combine information on chemical composition of plant tissues with spatial information. The contributions from the building blocks of the cell walls in the Raman spectra of plant tissues can vary in the microscopic sub-structures of the tissue. Here, we discuss the analysis of 55 Raman maps of root, stem, and leaf tissues of , using different spectral contributions from cellulose and lignin in both univariate and multivariate imaging methods.

Physiological influence of silica on germinating pollen as shown by Raman spectroscopy.

The process of silicification in plants and the biochemical effects of silica in plant tissues are largely unknown. To study the molecular changes occurring in growing cells that are exposed to higher than normal concentration of silicic acid, Raman spectra of germinating pollen grains of three species (Pinus nigra, Picea omorika, and Camellia japonica) were analyzed in a multivariate classification approach that takes into account the variation of biochemical composition due to species, plant tissue structure, and germination condition. The results of principal component analyses of the Raman spectra indicate differences in the utilization of stored lipids, a changed mobilization of storage carbohydrates in the pollen grain bodies, and altered composition and/or structure of cellulose of the developing pollen tube cell walls.

Survival of the Fittest: Competitive Co-crystal Reactions in the Ball Mill.

The driving forces triggering the formation of co-crystals under milling conditions were investigated by using a set of multicomponent competitive milling reactions. In these reactions, different active pharmaceutical ingredients were ground together with a further compound acting as coformer. The study was based on new co-crystals including the coformer anthranilic acid.