Abstract The main problem in oncology is the lack of specificity of action of many antitumor drugs, which creates a need for the development of new technologies providing targeted delivery of drugs to cancer cells. Nanogels from chitosan and hyaluronic acid were obtained using cross-linking reagents. To obtain nanogels, various ratios of chitosan and hyaluronic acid (1:1.25, 1:2.5, 1:5, 2:1, 5:1) were used. As a result, nanogels of various sizes and morphologies were obtained. Electron microscopy showed that nanogels are polydisperse and have a size of 100—400 nm. Dynamic light scattering method established that the obtained nanogels are positively charged and have a surface potential of (+) 5.3 ±0.31. Stability of nanogels in water, fetal bovine serum, and saline, as well as that of nanogels-dinitrosy iron complex was studied. Results of dynamic light scat-tering showed that nanogels retain high stability and are resistant to aggregation in water and in physiologi-cal solutions. Cytotoxicity of these nanogels was studied using the fluorescence method, which showed that nanogels in the growth medium at 20, 40, and 60 % are compatible with cells, with cell viability maintained at levels ranging from 100 to 78 %. The nanogels-dinitrosy iron complex has been proved to suppress the viability of prostate cancer cells 1.5 times. These results underscore the potential of nanogels in improving cancer treatment through enhanced targeted delivery and inhibition of cell viability of cancer cells.
Abstract Four ionic Ni(II) complexes containing the [Ni(H im ) 6 ] 2+ (H im = imidazole) complex cation were prepared: [Ni(H im ) 6 ](CO 3 )·5H 2 O ( 1 ), [Ni(H im ) 6 ]( ac ) 2 ·H 2 O ( 2 , ac = acetate), [Ni(H im ) 6 ](NO 3 ) 2 ( 3 ), and [Ni(H im ) 6 ]SiF 6 ( 4 ); complexes 2 and 4 are new. The prepared complexes were characterized chemically and spectroscopically. Results of X-ray single crystal studies have shown that all four complexes exhibit ionic crystal structures comprising [Ni(H im ) 6 ] 2+ complex cations, the respective anion(s), and in case of 1 and 2 , additional solvate water molecules. Ni(II) central atoms in all complexes 1 — 4 are hexa-coordinated by six N-atoms originating from monodentate H im ligands. While in 1 and 4 the NiN 6 chromophore is quite a regular octahedron with only one independent Ni—N bond, as imposed by local symmetry, in 2 and 3 the octahedra are slightly deformed. On the other hand, significant differences were observed in the orientation of H im rings within the respective coordination polyhedra.
Two novel potent perfluorophenylhydrazone derivatives, 1-((5-nitrothiophen-2-yl)methylene)-2-(per- fluorophenyl)hydrazine, (I), and 1-((5-nitrofuran-2-yl)methylene)-2-(perfluorophenyl) hydrazine, (II), are introduced, with suggested improvement by further design. Their multitarget structures and features have been combined to create potential AD therapeutics. Crystals (I) and (II) are molecules with two rings and a hydrazone part at the centre of the molecule. They were synthesised and characterised using elemental and spectroscopic (1H-NMR) analyses and their crystal structures were determined using the single-crystal X-ray diffraction method. The structures crystallise in the monoclinic space group with Z = 2 and Z = 4 molecules per unit cell. Compound (I) crystallises as a dimer in the non-centrosymmetric space group, while compound (II) crystallises as a racemate in the centrosymmetric space group. The "absolute configuration and conformation for bond values" were not derived from anomalous dispersion (rmad). The crystal structures reveal diverse non-covalent interactions such as intra- and inter-hydrogen bonding, pi-ring - pi-ring, C-H - pi-ring interactions. The expected stereochemistry of hydrazone atoms C7, N2, and N1 was confirmed for compounds (I) and (II). Both molecules possess a "boat conformation" resembling a 6-membered ring. Results of the single crystal studies were reproduced using the Hirshfeld surface analysis, Gaussian software, and QTAIM contour mapping.
Four ionic Ni(II) complexes containing the [Ni(Him)6]2+ (Him = imidazole) complex cation were prepared: [Ni(Him)6](CO3)& centerdot;5H2O (1), [Ni(Him)6](ac)2 & centerdot;H2O (2, ac = acetate), [Ni(Him)6](NO3)2 (3), and [Ni(Him)6]SiF6 (4); complexes 2 and 4 are new. The prepared complexes were characterized chemically and spectroscopically. Results of X-ray single crystal studies have shown that all four complexes exhibit ionic crystal structures comprising [Ni(Him)6]2+ complex cations, the respective anion(s), and in case of 1 and 2, additional solvate water molecules. Ni(II) central atoms in all complexes 1-4 are hexa-coordinated by six N-atoms originating from monodentate Him ligands. While in 1 and 4 the NiN6 chromophore is quite a regular octahedron with only one independent Ni-N bond, as imposed by local symmetry, in 2 and 3 the octahedra are slightly deformed. On the other hand, significant differences were observed in the orientation of Him rings within the respective coordination polyhedra.
Aflatoxin M 1 (AFM 1 ), which is a hydroxylated metabolite of aflatoxin B 1 , can be irreversibly bound to casein micelles and thus, its higher content is measured in cheese than in the original milk. The present study describes validation of a reliable and rapid method for AFM 1 content determination in cheese applied to 36 kinds of cheese sold in Slovakia during the spring of 2024. The method consisted of three basic steps: extraction of AFM 1 from cheese, purification of extracts using immunoaffinity columns, and determination of AFM 1 content by high performance liquid chromatography with fluorescence detection. Suitability of the method was proved by the limits of detection and quantification equal to 2.0 and 6.0 ng/kg, respectively, which is in accordance with the limits set by European legislation for analytical procedures for AFM 1 determination in milk. Accuracy of the method was determined using a recovery test, spiking cheese with AFM 1 , and varied between 87.8 and 100.5 %. Precision was confirmed by low relative standard deviations, 0.3—7.9 %, and Hor- Rat values (0.01—0.32) of the results obtained on different days. Experiments showed the AFM 1 content in all cheese to be below the limit of quantification, which indirectly confirmed the absence of AFM 1 in milk as raw material. However, AFM 1 contamination of milk is expected to increase due to global warming in future; therefore, AFM 1 contamination should be an essential part of current food safety issues.
