Role of the Protein Corona Derived from Human Plasma in Cellular Interactions between Nanoporous Human Serum Albumin Particles and Endothelial Cells

The presence of a protein corona on various synthetic nanomaterials has been shown to strongly influence how they interact with cells. However, it is unclear if the protein corona also exists on protein particles, and if so, its role in particle-cell interactions. In this study, pure human serum albumin (HSA) particles were fabricated via mesoporous silica particle templating. Our data reveal that various serum proteins adsorbed on the particles, when exposed to human blood plasma, forming a corona. In human umbilical vein endothelial cells (HUVECs), the corona was shown to decrease particle binding to the cell membrane, increase the residence time of particles in early endosomes, and reduce the amount of internalized particles within the first hours of exposure to particles. These findings reveal important information regarding the mechanisms used by vascular endothelial cells to internalize protein-based particulate materials exposed to blood plasma. The ability to control the cellular recognition of these organic particles is expected to aid the advancement of HSA-based materials for intravenous drug delivery

Pore Condensation in Glycerol Dehydration : Modification of a Mixed Oxide Catalyst

Pore condensation has been suggested as an initiator of deactivation in the dehydration of glycerol to acrolein. To avoid potential pore condensation of the glycerol, a series of WO3supported on ZrO2 catalysts have been prepared through thermal sintering, with modified pore systems. It was shown that catalysts heat treated at temperatures above 800 °C yielded suitable pore system and the catalyst also showed a substantial increase in acrolein yield. The longevity of the heat-treated catalysts was also improved, indeed a catalyst heat treated at 850 °C displayed significantly higher yields and lower pressure-drop build up over the 600 h of testing. Further, the catalyst characterisation work gave evidence for a transition from monoclinic to triclinic tungsten oxide between 850 and 900 °C. There is also an increase in acid-site concentration of the heat-treated catalysts. Given the improved catalyst performance after heat-treatment, it is not unlikely that pore condensation is a significant contributing factor in catalyst deactivation for WO3 supported on ZrO2 catalysts in the glycerol dehydration reaction