Complete well aspiration

Hi there!

I’m trying to write a script for running an ELISA assay on FluentControl. One of the most critical parts of the ELISA is aspirating away as much liquid from the each well of the 96-well plate as possible without touching the bottom of the wells.

Anyone have any tips on this? So far, I’ve been editing the Z-Max in the Positions/Teaching settings of the ELISA plate, but occasionally the fixed pipette tip will still scrape the bottom of the wells. Thanks in advance!

i would advise on aspirating slowly, from the corner of the well (not the middle),

this should allow you to aspirate 99%+ of the volume in the well,

i would also advise on verifying the Zmax - optimum teaching is to have Z max about 0.5 mm above the actual bottom of the well

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Do keep in mind that the FCA validation from Tecan allows “play” for Z-height differential across all 8 tips. I believe they must be within 0.3mm, but don’t quote me.

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Are you using an 8-channel? If so I recommend perhaps a feedback loop of the following sort

  1. Define an acceptable Residual volume (for example ~15uL is okay to leave behind in the well)
  2. Define a Removal Volume variable ( would use an array tbh )
  3. Define a Detected Volume Variable ( would use an array tbh )
  4. Define a Detected Volume Variable
  5. Setup logic so that the removal volume always leaves behind the residual volume
  6. Pipette Action: FCA Liquid Level Detection
  7. Assign detected volume
  8. Calculate removal volume
  9. Assign Removal volume
  10. Pipette Action: Remove the Volume

I find that detection helps with your problem a lot.

Some major caveats, make sure your container definition is good. Second play around with the residual volume. User a Variable Pipetting Loop to control for variable sample numbers.

Cheers

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Thank you for the suggestions, everyone! I started with @Optimize 's idea, as it was the easiest to implement, and coupled with a little more tweaking of the Z-max, it worked!

Aspirating from the corner of the well has so far been successful in aspirating away most of the volume in the well without scraping the bottom of the wells. I brought this up to my manager, who mentioned that it’s highly possible that the bottom of the wells are convex, rather than flat, as I’d previously thought.