Table 1.
Liposome characterization.
Fig 1.
Orthogonal images from confocal laser scanning microscopy of S. aureus biofilm treated with liposomes.
Liposomes including A) cationic multilamellar vesicle (+MLV), B) cationic unilamellar vesicle (+ULV), C) anionic multilamellar vesicle (-MLV) and D) anionic unilamellar vesicle (-ULV), were labeled red (DiI) and biofilm was stained green (SYTO-9). The middle square image in the blue frame was the 3D projection of five layers in the biofilm centre from the z-stack with the mode of maximum intensity, including the layer with the maximum integrated fluorescent density of the green channel. The images on the top and right side were the central layer from the y-stack and x-stack respectively. The scale bar represented 10μm.
Fig 2.
Orthogonal images from confocal laser scanning microscopy of P. aeruginosa biofilm treated with liposomes.
Liposomes including A) cationic multilamellar vesicle (+MLV), B) cationic unilamellar vesicle (+ULV), C) anionic multilamellar vesicle (-MLV) and D) anionic unilamellar vesicle (-ULV), were labeled red (DiI) and biofilm was stained green (SYTO-9). The middle square image in the blue frame was the 3D projection of two layers in the biofilm centre from the z-stack with the mode of maximum intensity, including the layer with the maximum integrated fluorescent density of the green channel. The images on the top and right side were the central layer from the y-stack and x-stack respectively. The scale bar represented 10μm.
Fig 3.
Liposomal distribution in S. aureus biofilm.
The y-axis represents the integrated fluorescent density of the red channel (liposomes) normalized by that of the green channel (biofilm), reflecting the amount of liposomes per unit of biomass in each layer of the biofilm. The x-axis indicates the z-position of the layers in biofilm, where the location of the top surface of biofilm was assigned as zero. +MLV: cationic multilamellar vesicle; +ULV: cationic unilamellar vesicle;-MLV: anionic multilamellar vesicle;-ULV: anionic unilamellar vesicle.
Fig 4.
Liposomal distribution in P. aeruginosa biofilm.
The y-axis represents the integrated fluorescent density of the red channel (liposomes) normalized by that of the green channel (biofilm), reflecting the amount of liposomes per unit of biomass in each layer of the biofilm. The x-axis indicates the z-position of the layers in biofilm, where the location of the top surface of biofilm was assigned as zero. +MLV: cationic multilamellar vesicle; +ULV: cationic unilamellar vesicle;-MLV: anionic multilamellar vesicle;-ULV: anionic unilamellar vesicle.
Fig 5.
Comparison of liposomal distribution in S. aureus and P. aeruginosa biofilms.
Comparison of liposomal distribution in both S. aureus and P. aeruginosa biofilms measured by Liposome Quantity, reflecting the amount of liposomes per unit of biomass in the most intensive section of biofilm, and Distance, representing how close the majority of liposome approached to the core of biofilm. The histogram displayed medians with ranges, and the comparison was carried out by Kruskal-Wallis test with Mann-Whitney test for post-hoc. **: P<0.01; NS: no statistic significance, P>0.05; +MLV: cationic multilamellar vesicle; +ULV: cationic unilamellar vesicle;-MLV: anionic multilamellar vesicle;-ULV: anionic unilamellar vesicle.
Table 2.
Distribution of liposomes in S. aureus and P. aeruginosa biofilm.
Fig 6.
Comparison of anti-biofilm effect of liposomes against S. aureus and P. aeruginosa biofilms.
Comparison of anti-biofilm effect of liposomes against both S. aureus and P. aeruginosa biofilms tested by alamarBlue assay. The histogram displayed medians with ranges, and the comparison was carried out by Kruskal-Wallis test with Mann-Whitney test for post-hoc. *: P<0.05; **: P<0.01, compared to the untreated control; +MLV: cationic multilamellar vesicle; +ULV: cationic unilamellar vesicle;-MLV: anionic multilamellar vesicle;-ULV: anionic unilamellar vesicle.
Table 3.
Relative viability of S. aureus and P. aeruginosa biofilm at five-minute and 24-hour exposure.