Dispense TADMS (ELISA)

Hi Everyone,

I have been working on an ELISA assay on our Hamiltons and there is a dispense of 50 µL of detection reagent into empty wells of a 96-well plate from 5mm fixed height using 300µL unfiltered tips on the 1000µL channels.
I have tried the TADM programmers manual, but not found much help there.
The dispense TADM of this transfer and the liquid class settings are below. I was wondering, is the messiness on the right of the graph something that can be optimised? other than changing the dispense speed i don’t really know what to change that would effect this TADM?

image

I have all the aspirate TADMs looking beautiful, but the dispense TADMs i am having a much tougher time getting to look good.
Thank you for any help and suggestions,
Ewan

1 Like

I think the main parts of the dispense curves look very consistent. The variability at the end of the dispense corresponds to the blowout volume of air which is set to 30µL. As there is some residual liquid left in the tip, this behavior is expected. If you set guardbands, then I would just set them to be wider at this section of the curve. The more critical parts are where the liquid is flowing and continues to flow out of the tip.

4 Likes

I hope it’s cool that I changed the topic name to include (ELISA) to make it more specific

I love the TADM graphs btw, I’m surprised I don’t see them more often

3 Likes

This is fantastic, thank you so much Eric. I don’t suppose you have a similar diagram of the aspiration stage as well? Just of reference.
What differences might you expect to see between a dispense jet and dispense surface TADM graph?

No problem Stefan, if you can make the topic name more specific, and it helps others find it and help them, then just go for it.

See below for the aspirate pressure profile. You can find these images and more info in the Liquid Handling reference guide.

5 Likes

To pile onto this, I also am surprised…granted I haven’t used them heavily at all :smiley:. Does anybody have any use cases for TADM?

I think troubleshooting cases like this especially with heterogenous or phase separated mixtures it is an extra set of data in addition to an Artel or eyeballing it

2 Likes

@Kastronaut One use case we have is to use TADM to separate centrifuged blood-samples based on phases. For us we were interested in keeping the serum portion only and TADM can trigger an error and an automatic recovery once you hit the gel in a microtainer tube.

I know that you can also use TADM to determine what kind of liquid you are pipetting based on previous curves.
We are also exploring the possibility to use TADM to optimize the liquid classes more easily, but we haven’t got really far with this one.

2 Likes

I sometimes have tubes with peletted tissue and ethanol on top which I need to remove. There TADM works great :slight_smile:

2 Likes

I use for troubleshooting. Can see if a tip got clogged, if it ran out of liquid, ran into some bubbles, or bottomed out and got occluded for examples.