Difference between revisions of "French Press"

Revision as of 12:22, 4 May 2009

Prepare the Cell (Not Auto-Fill)

1. Invert cell on black stand without base piece. Remove piston to fill line
2. Pour in sample, replace base and place back on the press. Ensure valves are tightened

Loading Sample

1. With the back valve open and the bottom valve closed insert tubing into sample
2. Set French Press to Down and start. Suction caused by the piston moving out of the cell will bring sample into the cell
3. When the base is at the bottom close the intake valve and stop the Press

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

Cleaning/Storage

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