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Chapter 2
2.6.3. SEM Analysis of surfaces to confirm biofilm removal via sonication
All surfaces were examined using SEM before and after sonication for a set
of coupons from 1 of the triplicate runs for each strain. SEM was
performed on a set of coupons not exposed to sonication to assess biofilm
formation on the surface. Post-sonication SEM analysis was performed to
assess completeness of removal of cells from the surface. The results
indicate that all biofilm cells were removed from the surface after
sonication for 12 of the 13 strains examined.
However the S. Typhimurium LT2 biofilm was not effectively removed from
the surface using the sonication conditions described. Figure 2.5 displays
the SEM Images of S. Typhimurium LT2 biofilm attached to glass, steel,
polycarbonate, tile and concrete after sonication for 7 minutes at 20 kHz.
Figure 2.6 displays complete removal of S. Typhimurium SL1344 from the
surfaces via sonication using the same conditions.
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