French Press

From Bridges Lab Protocols
Jump to: navigation, search

Prepare the Cell (Not Auto-Fill)

  1. Pour in sample, replace base and place back on the press. Ensure valves are tightened

Loading Sample

  1. Set French Press to Down and start. Pour sample into cylinder followed by the piston.
  2. Ensure that the piston is lubricated with glycerol.
  3. Place cylinder with piston into the French Press instrument from the back, making sure that the piston's lever is orthogonal to the brace screws.
  4. Position the valves such that they are accessible to your hands.

Lysing Sample

  1. For bacteria 15 000 psi of cell pressure is sufficient. For a 1cm cell this corresponds to about 1100 psi on the gauge (see chart)
  2. Turn black knob all the way to the left
  3. Set Press to High and ensure both valves are securely closed
  4. Start the press. The cell will move until it encounters pressure and will stop moving (the motor will still be running)
  5. Slowly turn the knob until the gauge pressure reads desired pressure
  6. Slowly open valve until sample comes out, keep an eye on the pressure and make sure it doesn’t drop. Continue until piston is fully depressed. Close bottom valve
  7. Reload sample if necessary


  1. Disassemble and rinse all parts with 70% ethanol then distilled water
  2. Normally cells are stored at 4C to reduce sample heating