For pellets larger than 0.5 mL and ≤2 mL, measure and adjust the volume before transferring.
- Pre-rinse a pipette (10 or 25-mL) with elution buffer
- Resuspend the packed pellet using vortex, pipette mixing or a combination
- Rinse the sides of the conical portion of the tube while pipette mixing
- Draw up the total volume of concentrate into the pipette
- Measure the volume in the pipette; release the resuspended volume back into the centrifuge tube
- Add reagent water to reach the total resuspended concentrate volume already determined OR divide the actual total resuspended concentrate volume evenly over the correct number of Leighton tubes (2 to 4 depending on the pellet size)
- Be sure the pellet is still resuspended; pipette it into a labeled Leighton tube
- Resuspend the packed pellet, draw up another subsample volume, pipette into another Leighton tube
- Continue until all required subsamples have been transferred to a Leighton tube
- Calculate the volume of reagent water rinses [per Leighton tube: 10 mL - mL transferred; divide volume between 2 rinses]
For pellets >2 mL, aspirate to the total resuspended volume calculated and transfer 5 mL of resuspended pellet into each of 4 Leighton tubes. Select the Video Link to view the procedure.