Software overview - 11.6 Prepare grids workflow - preload sample

This stage is not time critical. It consists of 3 tasks; replacing the dispenser cleaning pad if necessary, loading the dispenser cleaning vial with methanol and loading the sample. 

11.6.1 Dispenser cleaning pads


When necessary, replace the wipe pads. The need to replace the dispenser tip cleaning pad will arise through use. chameleon software will prompt you to replace the pads when necessary but you may replace them now if you prefer.  

  1. Remove the magnetic metal covering.
  2. Remove the old dispenser pads. 
  3. Insert the new, uncut dispenser pad, followed by the new cross-cut dispenser pad. 
  4. Replace the magnetic, metal covering.
  5. Note: the order of the dispenser pads is important as the dispenser will protrude through the cuts in the top pad.  

Ensure that the magnetic keeper is correctly located on the base after replacing the wipe pad.  

fig:If the keeper is out of position the dispense head may be damaged.  

The star nose wipe must be placed uppermost, else damage to the dispenser tip may occur. 

11.6.2 Dispenser cleaning vial

Methanol is used during the dispenser cleaning and setup cycles.  

Load a new clean dispenser cleaning vial and fill it with methanol, using the squeeze bottle supplied. 

Wear appropriate PPE to protect against accidental spillage of methanol when refilling the vial on the instrument. 


NOTE: Do not use Eppendorf vials, this may result in damage to the dispenser head. 

Tick the box on chameleon's software to confirm that you have done this, or Continue is not enabled. 


11.6.3 Load sample

The temperature-controlled sample position holds a small vial in a block with a user-controlled temperature in the range of 4-37°C.  

To avoid cross-contamination, you must replace the vial each time a new sample is loaded. 

Between 5-20µl of sample should be loaded into the sample vial. 

  1. Open the upper doors to load a clean sample vial.
  2. Clean the sample vial with compressed air. It must be clean of dust.
  3. Put the sample vial in the sample holder.
  4. Pipette the sample into the vial. At least 2 µL more than the Volume to Aspirate is required, so the minimum volume that should be loaded into the instrument is 5 µL. 
  5. Close the doors.
  6. Set the temperature of the sample holder between 4°C and 37°C. Its default value is 4°C.
  7. Set the Volume to Aspirate as needed. The minimum recommended volume to aspirate is 3 µL (also the default). 
  8. The Previous Sample dropdown can be used to automatically input sample details that have been used previously. These can then be modified if needed to create a new sample which will be available in future sessions. The Previous Sample dropdown will display the most recent three months of samples in timestamp order. Alternatively, input the details for your new sample.
  9. Once these steps are complete, press Continue.

Next article - Software overview - 11.7 Prepare grids workflow - preload cryogens & button