In this paper, we report the synthesis, characterization (FT-IR, XRD, BET, HR-TEM) and bioevaluation of a novel γ-aminobutiric acid/silica (noted GABA-SiO₂ or γ-SiO₂) hybrid nanostructure, for the improved release of topical antibiotics, used in the treatment of Staphylococcus aureus infections. GABA-SiO₂ showed IR bands which were assigned to Si-O-Si (stretch mode). The XRD pattern showed a broad peak in the range of 18-30° (2θ), indicating an amorphous structure. Based on the BET analysis, estimations about surface area (438.14 m²/g) and pore diameters (4.76 nm) were done. TEM observation reveals that the prepared structure presented homogeneity and an average size of particles not exceeding 10nm. The prepared nanostructure has significantly improved the anti-staphylococcal activity of bacitracin and kanamycin sulfate, as demonstrated by the drastic decrease of the minimal inhibitory concentration of the respective antibiotics loaded in the GABA-SiO₂ nanostructure. These results, correlated with the high biocompatibility of this porous structure, are highlighting the possibility of using this carrier for the local delivery of the antimicrobial substances in lower active doses, thus reducing their cytotoxicity and side-effects.
Keywords: Anti-staphylococcal activity; Gamma-aminobutyric acid; Improved MIC; Silica nanopowder.
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