Detection of Biofilm Disassembly Through a Dispersion Assay

Record the OD₆₀₀ values from the overnight biofilm plate on the plate reader by setting the control well as blank. Next, aspirate the culture medium using a vacuum line without disturbing the adherent population on the plastic surface. Gently wash the wells twice with 200 microliters of sterile PBS.

After washing with PBS at 130 microliters of the prewarmed PBS, PBS with glucose, PBS with bile salts, and PBS with bile salts and glucose to each of the three wells. Then incubate the plate at 37 degrees Celsius for 30 minutes. After 30 minutes, remove the plate from the incubator. Pipette the supernatant out to a fresh sterile 96-well plate.

Finally, prepare 1 to 10 serial dilutions of the supernatant with PBS in the 96-well plate or in a dilution block. Then use a multichannel pipette to transfer 5 microliters of each dilution on LB agar plates. Incubate the plates at 37 degrees Celsius overnight. The next day, count the number of colonies.