New Nanostructured Materials Based on Mesoporous Silica Loaded with Ru(II)/Ru(III) Complexes with Anticancer and Antimicrobial Properties

Abstract

A new series of nanostructured materials was obtained by functionalization of SBA-15 mesoporous silica with Ru(II) and Ru(III) complexes bearing Schiff base ligands derived from salicylaldehyde and various amines (1,2-diaminocyclohexane, 1,2-phenylenediamine, ethylenediamine, 1,3-diamino-2-propanol, N,N-dimethylethylenediamine, 2-aminomethyl-pyridine, and 2-(2-aminoethyl)-pyridine). The incorporation of ruthenium complexes into the porous structure of SBA-15 and the structural, morphological, and textural features of the resulting nanostructured materials were investigated by FTIR, XPS, TG/DTA, zeta potential, SEM, and N2 physisorption. The ruthenium complex-loaded SBA-15 silica samples were tested against A549 lung tumor cells and MRC-5 normal lung fibroblasts. A dose-dependent effect was observed, with the highest antitumoral efficiency being recorded for the material containing [Ru(Salen)(PPh3)Cl] (50%/90% decrease in the A549 cells’ viability at a concentration of 70 μg/mL/200 μg/mL after 24 h incubation). The other hybrid materials have also shown good cytotoxicity against cancer cells, depending on the ligand included in the ruthenium complex. The antibacterial assay revealed an inhibitory effect for all samples, the most active being those containing [Ru(Salen)(PPh3)Cl], [Ru(Saldiam)(PPh3)Cl], and [Ru(Salaepy)(PPh3)Cl], especially against Staphylococcus aureus and Enterococcus faecalis Gram-positive strains. In conclusion, these nanostructured hybrid materials could represent valuable tools for the development of multi-pharmacologically active compounds with antiproliferative, antibacterial, and antibiofilm activity.

Synthesis of CoFe2O4 through Wet Ferritization Method Using an Aqueous Extract of Eucalyptus Leaves

“…The antimicrobial activity of the obtained cobalt ferrite nanoparticles has been assessed against four bacterial and one fungal standard strain, i.e., Staphylococcus aureus ATCC 25923, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853, and Candida albicans ATCC 10231, at a density of 0.5 McFarland. The selected strains have been tested both in planktonic and biofilm growth states, by using qualitative (adapted disk diffusion method allowing the quantification of growth inhibition zones diameters on solid agar) and quantitative (broth microdilution method and violet crystal microtiter allowing to establish the minimal inhibitory concentration-MIC and minimal biofilm inhibitory concentration-MBIC) assays [32,33].…”

“…The lowest concentrations inhibiting the microbial growth revealed by the absence of turbidity for the planktonic growth and the absence of the blue color for the biofilm growth have been noted as MIC and respectively, MBIC. The assays were performed in duplicate [32,33].…”

Silica-Based Materials Containing Inorganic Red/NIR Emitters and Their Application in Biomedicine

“…The silanol group can hydrolyze similarly to TEOS with the formation of a RuL' 2 L-Si-(O-Si-) bond type. In this case, coating of pre-synthesized particles and simultaneous hydrolysis of the complex and silane are possible; (b) surface modification of silica particles with groups able to bind ruthenium complexes [206][207][208][209][210][211][212][213].…”