Y-Direction Dispense on The Fly

Hamilton (Venus)
1

Dear Community,
I was wondering if anyone has successfully initiated a “dispense on the fly” in the Y direction. We have reagents which remain in the tip and ideally we’d like to very quickly and crudely dispense back into the original tube it came in.

The current dispense or even dispense from a set height does not eliminate the issue of the 8 channels going back up to Z-Max and moving out of the way. If I could replicate the smooth movement and speed in the Y Direction this would not only be useful for this process but could also be beneficial for those needing reagent addition into tubes!

Let me know if anyone has any thoughts on this and I’d love to see what we can come up with/see if there is a solution!

2

I haven’t used it, but there was a post about the STAR Pipetting Tools Library where you can control the channel movements post dispense.

3

I was thinking the same thing, however you can set exact positions of the tip but I don’t think you can set a movement path while dispensing as far as I can tell

4

Do you mean a single channel dispensing on the fly in the Y-axis? Multiple channels parked at different Y coordinates?

Doing some research into parallel firmware commands/custom library creation as a possibility and wanted to get a better idea of what you had in mind.

5

Im thinking all 8 channels hovering above the tube in a tube holder and as they move in the x direction they dispense when over that specific sequence. each one of the 8 channels has the reagent inside the tip and then when it moves over the target it dispenses one by one in succession as it moves continuously in the x direction.

I have a valuable reagent in one of the flip top tubes in a career and it needs to be dispensed back as quickly as possible, I have been using jet dispense but the waiting for each pipette to dispense and then move back and then the time for the other tip to get into position to pipette is too long for the reagent to be outside of the stock container.

6

I wanted to re-kindle this as I think this is incredible useful for multi-dispense in the y direction/quickly dispensing volumes on time sensitive assays, and for pipetting in 384 or 1056 plates where multi dispenses need to occur in the Y-axis without needing to wait for the traverse position to be met.

Any thoughts @EricSindelar_Hamilton ?

The cherry on top would also be a library where we can pipetting while simultaneously moving in X or Y for plating agar or for washing cells in tandem with the tilt modules or integrated incubators!

7

I think you might have intended to tag someone else

8

Thanks just corrected that!

9

The X dimension “dispense on the fly” is coded into the firmware as an existing command. It likely won’t be possible to have this new function behave in the exact manner where it is dispensing at a discrete and predefined location but never stops.

It IS possible to create a submethod/library that allows the channels to move to a specific Y location, dispense, and then move onto the next without retracting fully in the the Z dimension.

I would start by defining in a very specific way how you want this to operate. Something like the following.

  1. Aspirate fluid from reservoir
  2. Without moving up in the Z move to adjacent X/Y location
  3. Dispense to wells
  4. Move to next Y location without retracting in the Z
  5. repeat until all y locations are dispensed
  6. increment X location without retracting in the z
    ETC.

Also include a description of the exact functionality you’d like.
For instance:
do you want the ability to identify plate locations?
Adjust the Z transverse heights to accommodate different plate heights?
Should they move in the Z before dispensing? dip into the wells to the bottom then retract to the modified transverse Z height?

Please also include an annotated picture of your deck layout with the locations you’re referencing called out.

There is a fair bit of development and testing that will need to take place to verify the system can do this safely.

1 Like
10

Thanks @JDesRo I’ll give it a shot with this info, I didn’t realize that the DOTF was as hard coded as it was!

11

Hi Zach, @JDesRo is correct that a firmware limitation would prevent one from performing such a y-movement during a dispense on the fly.

One other approach to help reduce the time for a multi-dispense process is to use a normal dispense step with a minimized z-move enabled. If you set the dispense height to the same height as the clearance height and have liquid following off, then you can eliminate the up/down movement of channel during the dispense. It will still stop for every dispense position though so it’s not the same as dispense on the fly. For higher-density plates, you could set your sequence in a serpentine fashion to again minimize any extra movement.

For this approach, it’s critical that the clearance height is indeed set to be physically above the container in order to prevent damage. Also, if you have a dispense step for any post-aliquots, make sure the minimize z-movement is disabled so the channels retract back to a safe height prior to movement to a different labware.

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