14. When the French press cell is empty, turn machine lever to
“Down” until returned to original position.
15. Place eluent collection bottle on ice in ice bucket, carefully
remove cell from the French press and place it upside-down
on the stand.
16. Loosen the pressure release knob to release the vacuum (see
Note 53) and remove the base unit.
17. Pull the piston until it is again at the “max fill” line.
18. Repeat steps 9–17 until the entire cell suspension has been
passed through the French press cell a total of six times.
19. Smear a small amount of cell paste on a glass slide and check
breakage by acid-fast staining (see Note 54).
20. When finished, thoroughly clean French pressure cell unit by
completely disassembling unit, and washing each part with
broad spectrum disinfectant, distilled water, then 70% ethanol
(see Note 55).
21. Allow all parts to completely air-dry prior to storage.
Fig. 5 Labeled parts for assembly and use of French press cell. Figure used is
identical to that shown in the previous edition of this protocol chapter
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Megan Lucas et al.