Carolina 3M Petrifilm Aerobic Count Plates - Manual (Page 4)

3. With pipet perpendicular to the Petrifilm plate, place 1 mL of sample
onto the center of the bottom film (fig. 3). If necessary, samples can be
diluted with distilled water, liquid culture medium, or buffers with pH
between 6.6 and 7.2.* If antibiotics are to be added to the medium,
add them to the inoculating liquid at the working concentration.
Figure 3
4. Release the top film. Allow it to drop onto the bottom film. Do not roll
the top film down (fig. 4).
Figure 4
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