Vsevolod Frolov

Iron deficiency anemia continues to pose a significant global health burden, necessitating the development of improved therapeutic delivery systems. This study investigates novel composite materials composed of organosilicon hydrogels and cross-linked sulfobutyl ether beta-cyclodextrin (SBECD) nanoparticles for the oral delivery of iron compounds. Two types of cross-linked SBECD nanoparticles were synthesized using 1,6-hexamethylene diisocyanate. These nanoparticles were characterized by DLS, NTA, and FTIR and possess size around 200–300 nm and negative zeta-potential around −35 mV with molecular weight 150–200 kDa. Various hydrogel matrices, including plain PMSSO hydrogels and modified versions with amino groups or silicate cross-links, are also described. The hydrogels were evaluated for their iron sorption capacity (up to 44% loading efficiency) and release kinetics for 3 h. The results demonstrate that cross-linked SBECD nanoparticles significantly enhance iron sorption and provide sustained release under simulated physiological conditions. Mathematical modeling indicated that the Higuchi model best describes the iron release kinetics. The findings suggest that the proposed composite materials hold considerable promise for the treatment of iron deficiency anemia, offering an innovative approach to enhance therapeutic efficacy and minimize adverse effects.

In this study, we report the synthesis and characterization of aminated poly(methyl silsesquioxane)-based hydrogels ((AP/MS)SO-hydrogels) as potential enzyme-sensitive vehicles for antianemic drugs. The hydrogels were synthesized via sol–gel polymerization and functionalized with amine groups. Characterization techniques included Congo red assay, Brunauer–Emmett–Teller (BET) surface area analysis, scanning electron microscopy, elemental analysis, ¹³C NMR, ²⁹Si NMR, and ATR-FTIR spectroscopy and microscopy of hydrogels. The sorption of ferric chloride and ferrous D-gluconate, as well as complexes of ferrous D-gluconate with HPCD, was evaluated. Crosslinking of the gel with bifunctional agents was performed to create a new amide enzyme-sensitive bond, followed by infrared characterization of the crosslinked product. Trypsin-mediated degradation studies demonstrated the sensitivity of the hydrogel to enzymatic cleavage under model conditions. Iron release experiments in gastric and intestine-simulating media confirmed prolonged release. Overall, our findings suggest that aminated PMSSO-hydrogels hold promise as versatile and biocompatible carriers for targeted delivery of antianemic agents, warranting further exploration in preclinical and clinical applications.

Copper-based electrocatalytic materials play a critical role in various electrocatalytic processes, including the electroreduction of carbon dioxide and nitrate. Three-dimensional nanostructured electrodes are particularly advantageous for electrocatalytic applications due to their large surface area, which facilitates charge transfer and mass transport. However, the real surface area (RSA) of electrocatalysts is a crucial parameter that is often overlooked in experimental studies of high-surface-area copper electrodes. In this study, we investigate the roughness factors of electrodeposited copper foams with varying thicknesses and morphologies, obtained using the hydrogen bubble dynamic template technique. Underpotential deposition (UPD) of metal adatoms is one of the most reliable methods for estimating the RSA of highly dispersed catalysts. We aim to illustrate the applicability of UPD of lead for the determination of the RSA of copper deposits with hierarchical porosity. To find the appropriate experimental conditions that allow for efficient minimization of the limitations related to the slow diffusion of lead ions in the pores of the material and background currents of the reduction of traces of oxygen, we explore the effect of lead ion concentration, stirring rate, scan rate, monolayer deposition time and solution pH on the accuracy of RSA estimates. Under the optimized measurement conditions, Pb UPD allowed to estimate roughness factors as high as 400 for 100 µm thick foams, which translates into a specific surface area of ~6 m²·g⁻¹. The proposed measurement protocol may be further applied to estimate the RSA of copper deposits with similar or higher roughness.