The aim of the research was to develop new pectin-based hydrogels with excellent swelling properties. Superabsorbent hydrogels composed of high methylated pectin and partially neutralized poly(acrylic acid) was obtained by free radical polymerization in aqueous solution in the presence of crosslinking agent—N,N’-methylenebisacrylamide. The effect of crosslinker content and pectin to acrylic acid ratio on the swelling properties of hydrogels was investigated. In addition, the thermodynamic characteristic of hydrogels was obtained by DSC. Furthermore, the structure of pectin-based hydrogels was characterized by FTIR and GPC. It was also proved that poly(acrylic acid) is grafted on pectin particles. The results showed that introduction of small amount of pectin (up to 6.7 wt %) to poly(acrylic acid) hydrogel increase the swelling capacity, while further increasing of pectin ratio cause decrease of swelling.

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In this study, we present a modulated synthesis nanocrystalline defective UiO-66 metal−organic framework as a potential chloroquine diphosphate (CQ) delivery system. Increasing the concentration of hydrochloric acid during the modulated synthesis resulted in a considerable increase of pore volume, which enhanced the CQ loading in

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The desilication of dealuminated zeolite Y in NaOH/tetrabutylammonium hydroxide mixtures produces hierarchical zeolite Y containing a micropore system as well as mesopores of significant volume and surface. IR studies evidenced that a new kind of hydroxyls was formed if desilication was realized above 318 K. This new kind of acidic hydroxyls is characterized by IR band at 3600 cm−1. IR studies showed, that these new hydroxyls showed extremely high acidity. This was evidenced by very high frequency shifts of IR bands of OH interacting with probe molecules: CO and N2: ΔνnormalOnormalH···normalCnormalO =411 cm−1 and ΔνOH···N2 =164 cm−1, resp. These frequency shift are the highest in all the chemistry of zeolites including very strongly acidic dealuminated mazzite and steamed zeolite USY (ΔνnormalOnormalH···normalCnormalO =ca. 380 cm−1) indicating that 3600 cm−1 hydroxyls are the most acidic in all the zeolites.

The removal of uremic toxins from patients with acute kidney injury is a key issue in improving the quality of life for people requiring peritoneal dialysis. The currently utilized method for the removal of uremic toxins from the human organism is hemodialysis, performed on semipermeable membranes where the uremic toxins, along with small molecules, are separated from proteins and blood cells. In this study, we describe a mixed-linker modulated synthesis of zirconium-based metal−organic frameworks for efficient removal of uremic toxins. We determined that the efficient adsorption of uremic toxins is achieved by optimizing the ratio between −amino functionalization of the UiO-66 structure with 75% of −NH 2 groups within organic linker structure. The maximum adsorption of hippuric acid and 3-indoloacetic acid was achieved by UiO-66-NH 2 (75%) and by UiO-66-NH 2 (75%) 12.5% HCl prepared by modulated synthesis. Furthermore, UiO-66-NH 2 (75%) almost completely adsorbs 3-indoloacetic acid bound to bovine serum albumin, which was used as a model protein to which uremic toxins bind in the human body. The high adsorption capacity was confirmed in recyclability test, which showed almost 80% removal of 3-indoloacetic acid after the third adsorption cycle. Furthermore, in vitro cytotoxicity tests as well as hemolytic activity assay have proven that the UiO-66-based materials can be considered as potentially safe for hemodialytic purposes in living organisms.

Design of the catalytic properties and structure of zeolite materials play a key role in efficient transformation of biomass to sustainable chemicals. In the present study, we have designed theoretical and experimental approach for the production of acrylic acid (AA) from lactic acid (LA) over zeolite catalysts. Various BEA zeolites modified with metals (Co, Cu and Fe) were prepared using ion exchange and sonication methods. In the theoretical studies the metal M-O-M dimers have been found to be stable above oxygen bound with aluminium centers of BEA zeolite. The mechanism of direct LA dehydration over the Co-, Cu-and Fe-BEA zeolites has been proposed. Experimentally, the investigated catalysts trend in following byproduct formation: AA, propionic acid (PA), 2,3-pentanedione (2,3-PD) or acetaldehyde (AC). The best selectivity towards acrylic acid was achieved in the presence of the Co-and Cu-BEA catalysts prepared by the sonication method.