Hyaluronic acid is an excellent biocompatible material for in vivo applications. Its ability to bind CD44, a cell receptor involved in numerous biological processes, predetermines HA-based nanomaterials as unique carrier for therapeutic and theranostic applications. Although numerous methods for the synthesis of hyaluronic acid nanoparticles (HANPs) are available today, their low reproducibility and wide size distribution hinder the precise assessment of the effect on the organism. A robust and reproducible approach for producing HANPs that meet strict criteria for in vivo applications (e.g., to lung parenchyma) remains challenging. We designed and evaluated four protocols for the preparation of HANPs with those required parameters. The HA molecule was cross-linked by novel combinations of carbodiimide, and four different amine-containing compounds resulted in monodisperse HANPs with a low polydispersity index. By a complex postsynthetic characterization, we confirmed that the prepared HANPs meet the criteria for inhaled therapeutic delivery and other in vivo applications.

This paper is focused on the heterogeneously catalyzed transesterification (in a batch reactor) of vegetable oil, including the determination of leached metals. The oil was obtained from the short-season crop Camelina sativa. The reaction was catalyzed by mixed oxides, which were synthesized from Mg/Al hydrotalcites with built-in different types of divalent cations such as Mn, Ca, Co, Ni, and Fe. The various physicochemical properties like the structure by X-ray diffraction, acidity, basicity, and textural properties were measured and the effect of the added cation type on catalyst properties and activity was compared. A noticeable relationship between the cation type and catalytic activity in the transesterification reaction was observed. The highest ester content of 96.6 wt % after 7 h of transesterification was observed for catalysts with nickel and iron. The statistical analysis of results showed that the catalyst activity was mainly influenced by middle-temperature basic sites. The novelty lies in transesterification over five different heterogeneous catalysts—mixed oxides with added divalent metals at the same reaction conditions of C. sativa oil.

The conversion of ethanol into petrochemicals, such as ethyl and butyl acetate, butanol, hexanol, and so forth was studied. The conversion was catalyzed by Mg-Fe mixed oxide modified with a second transition metal (Ni, Cu, Co, Mn, or Cr). The main aim was to describe the influence of second transition metal on (i) the catalyst itself and (ii) reaction products such as ethyl acetate, butanol, hexanol, acetone, and ethanal. Moreover, the results were compared with the results of pure Mg-Fe. The reaction was carried out in the gas phase in a flow reactor with a weight hour space velocity of 4.5 h^-1 for 32 h at three reaction temperatures (280, 300, and 350 °C). The metals Ni and Cu in Mg-Fe oxide enhanced the ethanol conversion due to the population of active dehydrogenation sites. Despite the lower acido-basicity, Cu, Co, and Ni supported the yield of ethyl acetate, and Cu and Ni also promoted the yield of higher alcohols. Ni was related to the extent of the gasification reactions. Moreover, long-term stability (by leaching of metals) test was carried out for all catalysts (128 h).