Fig. 6. In vitro anti-biofilms effect of OHH NPs .The remaining biofilms were quantified by crystal violet staining. Biofilms were visualized by photographs (A) and biofilm biomass was determined by measuring the absorbance of 590 nm. (B). (C) Confocal fluorescence images of K.pneumoniae biofilms. (D) The corresponding statistical histogram showing the relative biofilm level. The group was used as the PBS, HMPB NPs(100 μg/mL), ofloxacin(10 μg/mL), OHH NPs (100 μg/mL) and OHH NPs + NIR(100 μg/mL).