Synthesis and characterization of Au@SiO₂core-shell nanostructures for improved antibiotic delivery systems

Gold nanoparticles (Au NPs) are widely used in medicine, however, their tendency to agglomerate can increase toxicity, which is a significant limitation. To counteract this, they are covered with a neutral coating, e.g. silica, which, among other things, allows their use as drug delivery systems. In this publication, Au@SiO₂ nanostructures were synthesized and functionalized with antibiotics - amoxicillin (AMOX) or mupirocin (MUP). The nanocarriers were characterized by spectroscopic, microscopic, wettability, cytotoxicity and percutaneous permeability tests. In addition, microbiological tests were performed, and the drug release rate of the nanostructure-antibiotic conjugates was investigated. Preliminary results showed that Au@SiO₂ can deliver even hydrophobic drugs and provide a prolonged release of the active substance. The nanocarriers showed low cytotoxicity and did not penetrate the skin. Moreover, conjugation with antibiotics indicates the potential of these nanomaterials as innovative components of hydrogel dressings for difficult-to-heal wounds.