Bioactive glass particles as multi-functional therapeutic carriers against antibiotic-resistant bacteria

The development of antibiotic resistance in pathogenic bacteria like Staphylococcus aureus calls for novel approaches to cope with the limited availability of effective antibacterial options. This work aims to develop a site-specific drug-delivery multifunctional vehicle with the ability to clear resistant bacteria while promoting the healing of the surrounding damaged tissue. The use of silver-doped microparticles (Ag-BG) is proposed as a platform to deliver vancomycin against MRSA, which under growth-arrested conditions exhibits resistance to vancomycin. Ag-BG caged vancomycin within the Ca-P deposits resulted from the ion exchange between surface and medium, with a loading efficiency higher than 50% after 6 h of uptake. The drug was always released above the minimum inhibitory concentration against MRSA. The Ag-BG@vanc conjugate presented strong antibacterial properties against metabolically impaired bacteria, which can tolerate high concentrations of vancomycin. Ag-BG@vanc was more lethal for MRSA than Ag-BG alone, due to its capability to synergize with antibiotics. The presence of Ca-P deposits and antibiotics at the Ag-BG surface did not compromise its biological properties since the Ag-BG@vanc conjugate still promoted the cell proliferation of human pre-osteoblast cells. These properties of multifunctional Ag-BG@vanc can provide new hope to fight antibiotic resistance and simultaneously promote bone regeneration holding great potential.

Automated summary

The study aims to develop a site-specific drug delivery multifunctional vehicle with the ability to clear resistant bacteria and promote tissue healing. The Ag-BG@vanc conjugate showed strong antibacterial properties against vancomycin-resistant MRSA strains, providing new hope in combating antibiotic resistance.