Hi!
Is there any way of having the ML prep mix samples at a faster speed than it pipettes?
I’d like to carry out sample and reagent transfers at a slower speed to achieve better accuracy, reproducibility and avoid bubbles (lots of detergent), but would also like mixing of samples to be somewhat faster, since accuracy is not an issue with mixing and I’d get better mixing with fewer cycles.
Thanks!
Hi!
As of version 3.2.0, the mix speed is still tied to pipetting speed for liquids and in the liquid overrides.
Having more granular control over the mix speed has been a frequently requested feature though and there is work in the pipeline ahead to expand on mixing capabilities, including separating out these parameters.
You can make a ticket and ask Hamilton MLP support to create a custom liquid class for you to import in. Give them all the pipetting specs needed, including the specific speed you want for mixing.
We’ve had to do this a lot as our mixing steps are critical.
we are considering to acquire a microlab prep for our team to prepare diluted compound plates in 96-well format mixing concentrated drugs from a stock plate at different concentrations into a plate with cell culture medium. we are planning to use the two single-pipette heads for this.
does anyone of you have experience how long it would take for the prep to pipette a full plate like this? this would entail basically 96 dispensing steps including mixing. 
Hi @Fwim, we recently did a study of transferring a small volume from 96 tubes to a plate with the two independent channels and no mixing that took a little under 16 minutes to complete.
I also just ran a plate to plate transfer with 300 µL each transfer, and no mixing that took a little over 17 minutes.
What volume of liquid are you looking to move, how many mix cycles and what volume of mix? I can get you a fairly accurate estimate.
hi @mrthorne,
many thanks for the swift response and the estimates. those are very useful.
we are planning to transfer 4 uL from the stock plate into about 100 uL at the target plate. for mixing, i think 3 mixes of ca. 50 uL should suffice.
In that case @Fwim, 96 wells, 4µL, 3 mixes at 50µl each with the two independent channels completes in about 16 minutes and 30 seconds.
As an alternative, that same activity with the 8MPH completes in about 4 minutes and 30 seconds. “Plate copy” activities are really things the 8MPH excels at, so some food for thought as you contemplate options.
thanks so much, @mrthorne . yeah, we’ve definitely started thinking about the 8-channel pipette as well. the speed gain seems to be very significant. but there are some situations where wells are not aligned for 8-channel pipetting and we’ll need the 2x 1-channel approach.