Mechanistic study on hydrodynamics in the mini-scale biphasic dissolution model and its influence on in vitro dissolution and partitioning

Sparkling plastic: Effects of exposure to glitter on the Mediterranean mussel Mytilus galloprovincialis

Microbeads and fragments have been widely studied, while glitter remains neglected by the literature although found in a variety product (e.g., body paints, nail polish, cosmetics, craft products). The main aim of this study was to assess the effects of different types and concentrations of glitter particles on Mytilus galloprovincialis after 7 days of exposure. The experiment was divided into a preliminary test and a confirmatory test. Our findings support the hypothesis for a link between concentration and type of glitter particles, percentage of recovery and oxidative stress in M. galloprovincialis. There was a significant correlation between particle length and percentage of particles recovered in water, suggesting that the digestive tract of M. galloprovincialis retains smaller particles more. In addition, we noted an increase in antioxidant defense induced by smaller particles. Moreover, certain types of glitter crumbled and shortened in length, resulting in higher levels of oxidative stress biomarkers. Finally, the star-shaped glitter particles had a different effect on oxidative stress biomarkers. Further studies are needed to clarify the toxic effects of glitter on aquatic organisms and to quantify its proportion to other microplastics in the environment.

A Rational Design of a Biphasic DissolutionSetup-Modelling of Biorelevant Kinetics for a Ritonavir Hot-Melt Extruded Amorphous Solid Dispersion

Biphasic dissolution systems achieved good predictability for the in vivo performance of several formulations of poorly water-soluble drugs by characterizing dissolution, precipitation, re-dissolution, and absorption. To achieve a high degree of predictive performance, acceptor media, aqueous phase composition, and the apparatus type have to be carefully selected. Hence, a combination of 1-decanol and an optimized buffer system are proposed as a new, one-vessel biphasic dissolution method (BiPHa+). The BiPHa+ was developed to combine the advantages of the well-described biorelevance of the United States Pharmacopeia (USP) apparatus II coupled with USP apparatus IV and a small-scale, one-vessel method. The BiPHa+ was designed for automated medium addition and pH control of the aqueous phase. In combination with the diode array UV-spectrophotometer, the system was able to determine the aqueous and the organic medium simultaneously, even if scattering or overlapping of spectra occurred. At controlled hydrodynamic conditions, the relative absorption area, the ratio between the organic and aqueous phase, and the selected drug concentrations were identified to be the discriminating factors. The performance of a hot-melt extruded ritonavir-containing amorphous solid dispersion (ritonavir-ASD) was compared in fasted-state dissolution media leading to different dissolution-partitioning profiles depending on the content of bile salts. An advanced kinetic model for ASD-based well described all phenomena from dispersing of the ASD to the partitioning of the dissolved ritonavir into the organic phase.