Fig. 6From: A synergistic bactericidal effect of low-frequency and low-intensity ultrasound combined with levofloxacin-loaded PLGA nanoparticles on M. smegmatis in macrophagesUltrasound combined with the LEV-NPs exhibited intracellular killing activity against M. smegmatis. The bacterial survival rate was determined using a CFU assay. The control group did not undergo ultrasound irradiation and the drug. The experiments were performed in triplicate; mean ± SD are shown. *P < 0.05, **P < 0.01Back to article page