Development of Metal Analogues of Prussian Blue@Silver Nanocomposites for the Treatment of Biofilm and Skin-Infections

Abstract

Silver-based nanocomplexes are promising antibacterial agents because of their ability to break the bacterial cell membrane, enhance oxidative stress, and damage bacterial DNA, offering potential alternatives to conventional antibiotics. Recently, Prussian blue analogues nanocomposites have gained attention due to their unique advantages, including biocompatibility, low cost, and easy structural modification to induce bioactivity. Herein, we developed different metal analogues of Prussian blue@silver [M^IIPB@Ag, M^II = Cu, Co, and Mn] nanocomposites for antibacterial applications. In vitro assays confirmed the utility of these materials in inhibiting Gram-negative and Gram-positive bacteria. The antibiofilm property of CuIIPB@Ag and MnIIPB@Ag was assessed by coating them on PDMS disk surfaces. The results show that CuPB@Ag (at 1600 μM) and MnPB@Ag (at 4000 μM) achieve approximately an 85% reduction in biofilm formation. In vitro cytotoxicity studies assessed by using the MTT assay support the biocompatibility of Cu^IIPB@Ag (up to 80% cell viability in 60 μM) and Mn^IIPB@Ag (up to 70% cell viability in 150 μM). Moreover, Cu^IIPB@Ag (at 1600 μM) and Mn^IIPB@Ag (at 4000 μM) eliminated in vivo skin infections in the preclinical rat model. These results highlight the potential of these metal analogues of Prussian blue@silver nanocomposites for the treatment of bacterial infections.