Acid‐soluble, undenatured, type I collagen (BSC) isolated, for the first time, from gilthead bream skin and the novel fabricated 3D porous wound dressing were analyzed for physicochemical and biological properties, in order to offer a safe alternative to commercial bovine collagen (BC) products. SDS‐polyacrylamide analysis confirmed the purity of BSC preparation. The hydroxyproline content and temperature of denaturation of BSC were lower than those of BC, in accordance with the structural data recorded by FT‐IR spectroscopy. However, certain concentrations of BSC stimulated the cell metabolism of L929 fibroblasts in a higher proportion than BC. The 3D wound dressing presented high porosity and low surface hydrophobicity that could help cell attachment and growth. The rapid biodegradation of BSC wound dressing could explain the improved in vitro cell migration and wound closure rate. In conclusion, the skin of gilthead bream from the Black Sea coast represented a valuable source for the biomedical industry, providing biocompatible, biodegradable collagen and 3D porous wound dressing, as novel material with enhanced wound healing activity.

Four mixed-ligand metal(II) complexes with the molecular formulae [M(ofl)(bipy)]NO3�H2O and [M(ofl)(phen)]NO3�H2O were synthesized by the reaction of Co(II) and Ni(II) with ofloxacin (Hofl) in the presence of 1,10-phenanthroline (phen) / 2,2`-bipyridine (bipy) (1:1:1 molar ratio). The data obtained from elemental analysis, molar conductance, spectral infrared, reflectance spectra and magnetic studies gave information about the coordination of the ligands and the geometry of the metallic ion. The results suggest that Hofl is deprotonated and bidentately bound to the metal ion through the pyridone oxygen and the carboxylato oxygen while phen and bipy act as neutral bidentate ligands coordinated through the nitrogen atoms. Tetrahedral geometry is proposed for all complexes. Thermal analysis data led to useful information concerning the composition, dehydration and thermal behaviour of the complexes. Ofloxacin and the metal complexes were tested for antibacterial activity and also for antioxidant activity. The variations of physicochemical parameters were monitored, which explain the antibacterial behaviour of these compounds. The interactions between metal complexes and bacterial receptors have lower energy values compared to the ofloxacin ligand. The molecular docking studies allow the identification of the biological target and the predictions of the bonds between the studied compounds and the receptors of E. coli (3t88), S. aureus (3q8u) and P. aeruginosa (4lkd).

Two novel fluorescent mesoporous silica-based hybrid materials were obtained through the covalent grafting of [4-hydrazinyl-7-nitrobenz-[2,1,3-d]-oxadiazole (NBDH) and N1-(7-nitrobenzo[c][1,2,5]-oxadiazol-4-yl) benzene-1,2-diamine (NBD-PD), respectively, inside the channels of mesoporous silica SBA-15. The presence of fluorescent organic compounds (nitrobenzofurazan derivatives) was confirmed by infrared spectroscopy (IR), X-ray photoelectron spectroscopy (XPS), thermal analysis (TG), and fluorescence spectroscopy. The nitrogen physisorption analysis showed that the nitrobenzofurazan derivatives were distributed uniformly on the internal surface of SBA-15, the immobilization process having a negligible effect on the structure of the support. Their antioxidant activity was studied by measuring the ability to reduce free radicals DPPH (free radical scavenging activity), in order to formulate potential applications of the materials obtained. Cytotoxicity of the newly synthesized materials, SBA-NBDH and SBA-NBD-PD, was evaluated on human B16 melanoma cells. The morphology of these cells, internalization and localization of the investigated materials in melanoma and fibroblast cells were examined through fluorescence imaging. The viability of B16 (3D) spheroids after treatment with SBA-NBDH and SBA-NBD-PD was evaluated using MTS assay. The results showed that both materials induced a selective antiproliferative effect, reducing to various degrees the viability of melanoma cells. The observed effect was enhanced with increasing concentration. SBA-NBD-PD exhibited a higher antitumor effect compared to SBA-NBDH starting with a concentration of 125 µg/mL. In both cases, a significantly more pronounced antiproliferative effect on tumor cells compared to normal cells was observed. The viability of B16 spheroids dropped by 40% after treatment with SBA-NBDH and SBA-NBD-PD at 500 µg/mL concentration, indicating a clear cytotoxic effect of the tested compounds. These results suggest that both newly synthesized biomaterials could be promising antitumor agents for applications in cancer therapy.

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High temperature heat storage is an active field of research, especially for addressing the intermittency issues of solar power. [...]