THE EFFECTIVE ANTI-BACTERIAL ACTIVITY OF SOME COPPER CONTAINING BORATE GLASSES

During the last years, the researchers' interest in glass has been continuously increasing, due to the fact that it was used as inorganic support in different composite biomaterials designed as scaffolds in tissue engineering. Therefore, several inorganic materials such as glasses have shown good bioactive and bacteriostatic activity. In this study, we investigated eight oxide glasses with different concentrations of oxides such as copper, strontium, aluminium, and boron, in terms of structural, bioactivity, and antimicrobial properties. Before the antibacterial assay, we measured the dissolution rate in the water of the glass system in order to test its local chemical durability. For the antimicrobial test, the following reference strains were used: Escherichia coli 25922, Staphylococcus aureus 6538P, Salmonela eneritidis 13076, and Bacillus cereus 11778. Our results show that the addition of copper oxide increased the dissolution gradient of the glass samples. Furthermore, the bacteriostatic effect manifested by the radius of the inhibition zone increased proportionally with the addition of CuO. The bacteriostatic effect of the samples was observed in both gram negatives and gram positives strains, with more significant effect on Staphylococcus aureus strain. The present study highlights the effectiveness of these copper containing glasses against some of known bacterial species capable of causing different types of soft or hard tissue infections in animals and humans.