Aims: To evaluate the antibacterial efficacy of silicate bioactive glass nanoparticles/collagen composites functionalized with tetracycline hydrochloride (TCH). Methods and Results: Different concentrations of tetracycline hydrochloride (TCH) were incorporated on silicate bioactive glass nanoparticles/collagen composites by dipping these biomaterials for 48h at 37 degrees C in a solution of simulated body fluid (SBF) plus 0 center dot 05, 0 center dot 20 or 0 center dot 35mgml(-1) of the antibiotic. TCH release was assessed in double-distilled water at 37 degrees C up to 72h. The antibacterial activity of the samples has been evaluated in two ways: inhibition zone test and plate count method. The experiments were performed in vitro up to 48h on four staphylococci strains (Staphylococcus aureus ATCC29213, ATCC25923, ATCC6538P and Staphylococcus epidermidis ATCC12228). The new composites were also tested for cytotoxicity on MG-63 human osteosarcoma cells. The results showed that the incorporation and release of TCH was dependent on the initial concentration of TCH in SBF. The biomaterials also inhibited the Staph.aureus cell growth even though the efficacy was similar for all concentration. On the other hand, no cytotoxic effects were found on osteoblast-like cells, even at the highest concentration. Conclusions: Considering all results, it can be concluded that the new composite acts as a suitable bioactive carrier of TCH and could have potential in the prevention of biomaterial related infections. Significance and Impact of the Study: The results suggest a potential application as wound dressing.