Fig. 1

Antibacterial activity of metronidazole (filled squares), LL-37 peptide (filled triangles), and ceragenins: CSA-13 (filled circles) and CSA-131 (filled diamonds) against Clostridium difficile (panel a). Antibacterial activity of ampicillin (cross), LL-37 peptide (filled triangles), and ceragenins: CSA-13 (filled circles) and CSA-131 (filled diamonds) against Propionibacterium acnes (panel b). Antibacterial activity of metronidazole (filled squares), LL-37 peptide (filled triangles) and ceragenins: CSA-13 (filled circles), and CSA-131 (filled diamonds) against Bacteroides fragilis (panel c). Antibacterial activity of magnetic nanoparticles (MNPs) functionalized by metronidazole (MNP@MET; empty squares), MNPs functionalized by LL-37 peptide (MNP@LL37; empty triangles), MNPs functionalized by CSA-13 (MNP@CSA13; empty circles) and MNPs functionalized by CSA-131 (MNP@CSA131; empty diamonds) when compared to activity of unmodified nanoparticles (MNPs; empty inverted triangles) against Bacteroides fragilis (panel d). Error bars represent standard deviations from three measurements. *indicates statistically significant (p ≤ 0.05) activity of tested agents compared to metronidazole (panels a and c), ampicillin (panel b) and uncoated MNPs (panel d)