Dynamic balance rack needs - deep well plate

I’m looking at implementing a new method on a Hamilton Autolys STAR (4+4 configuration)

We need to use the Hamilton on deck centrifuge to spin some deep well plates at max speed (6 gram imbalance tolerance with the Hamilton centrifuge).

There are two centrifuge steps – one requires a balance plate with 820ul liquid per well, the second requires a balance plate with 420ul per well.

Because the number of samples varies per run (min 1 max 24 – most commonly 16-24) – the number of wells that need to be filled in the balance plate varies.

Other labs, make the balance plate during the run – adding 820ul per well to match the number of samples – then they remove 400ul to create the balance rack for the second spin.

I’m wondering if anyone has any suggestions for better options? With a 4 channel this will take a while, and I’m trying to save some time for the method.

We have 1000ul tips on deck, so repeat pipetting wont help speed it up.

I’m not going to be much help, but your solution is the same as us. I can’ think of a better way so looking forward to other solutions!

I don’t know what your process looks like, but I wonder if it would be feasible to split your samples onto two plates prior to the centrifuge step so they would balance each other. I realize this might not be possible depending on the upstream and downstream work.


@DCurrier probably has the best solution. My only other thought would be to prepare balance#2 for 420uL fill volume using a fresh plate so it could be created asynchronously during spin #1.

I tried to find a average balance plate weight that satisfied the max imbalance of 5g for the most number of samples, but unfortunately it does not work well above n>12 samples. Above that number, you really need to create a new plate every time to balance the centrifuge - there’s just too much weight difference between those two volumes with that many samples.