Sealed, barcoded 96-well plates come in with one component of an experiment already pre-arrayed (1uL aqueous sample in PCR plate)
Add second component to each well. This volume is flexible but would ideally be consistent once we decide on a storage concentration. We can dispense anywhere from 100nL to 1uL depending on what concentration we store at. The second component might be the same for every well in the plate, or there might be a handful of different components per plate (let’s say a max of 10). There will be no consistent pattern for this second component, every plate will be different.
The second components have a max number of freeze/thaw lifespan, so thawing components that are not needed for that specific plate is not allowed.
If money were no object here’s the best that I’ve come up with, but I’m sure someone here can do better:
Echo
TTP comPOUND store
Sealer
Desealer
Capper/Decapper
Centrifuge
Acoustic Tubes
Software like Mosaic, etc for creating cherry pick files for Echo and pick lists for comPOUND store
User Creates desired plates in software and creates an “order.” Automation team receives plates associated with order and kicks off a run. Second component tubes are picked from tube store, thawed, spun, decapped. Plate desealed, they meet at the Echo and the magic gets done. Seal/cap/spin plate, return tubes to store, rinse and repeat. Looking at capacity for 40-50 plates/day.
The kicker is that the more I hear about Acoustic Tubes the less I like them. I have not used them myself, but not having Acoustic Tubes really muddies this process. You then need to create an intermediate plate (lots of waste for consumables and now I need an additional instrument, let’s say a Bravo). If I use Labcyte’s LDV plates then you only waste a few uL of material, but the cost for those plates (and only using ~10 wells!) is crazy. If I use the standard Labcyte plates then you waste ~15uL of material everytime you want to do a dispense.
What am I missing? Certainly something easier? Cost is no object at this point.
With that said, I don’t like intermediate plates or steps but I DISLIKE failure much more. If introducing an intermediate plate/step/equipment minimizes failures and the cost/frequency of failure is significant then you should stop fighting yourself and introduce an intermediate step. The other benefit is that gives you a continuous improvement project once you assess the safety and consistency of your process. An optional step that you can potentially improve or remove especially as new technologies come online.
I’m actually curious here, is the Echo that platform you’ve selected because of the low volumes you’re working with?
Good thoughts there about failure and also providing a continuous improvement project. I frequently jump to trying to design the perfect solution rather than a solution that works, but could be optimized in the future.
I picked the Echo and Acoustic Tubes because the process seems easiest. I like that it’s non-contact, and there’s no tip waste. There’s barely any consumable waste at all when those two are paired together, only 1 plate and plate seals. The tubes will be trashed eventually, but may be used ~10 times, so not too bad.
I’m open to other solutions, that one reason why I left the dispense volume variable. There’s only a handful of instruments that I’d trust 100nL dispenses with, but there’s a ton more at the 1uL dispense volume. I’m totally open to other instruments.
Really putting me on the spot for the instruments I trust at 100nL.
The Echo and the I.Dot are definitely on the shortlist. I have investigated the I.Dot and like it, but it somewhat suffers the same issues. I’d need to make an intermediate plate and those plates aren’t cheap. I believe their dead volume can be quite a bit lower than the standard Echo plates though, so that’s a positive. One downside is that if I start with an I.Dot I’m not sure there’s an improvement project except to buy an Echo to replace the I.Dot.
Thank you for sharing, it makes it useful for those in the future who are in the same predicament!
I heard through the grapevine that there’s an Echo competitor coming to market especially now that some of their core patents have expired. Does anyone know who that may be?
So maybe in the future you can swap that I.Dot with an Echo or a direct competitor to the Echo built off the same patents.
When transferring fluids with an Echo liquid handler, it’s important to consider that a 1 µL transfer can sometimes be challenging. This volume may disrupt the liquid’s meniscus, potentially affecting accuracy. In some cases, centrifugation between transfers might be necessary to restore the meniscus. To avoid these issues, we typically aim for lower volumes per individual transfer.
For our assay-ready plates, we implemented a comparable process using an intermediate plate approach. We use Labcyte LDV plates for this purpose. While comPOUND storage units are excellent, budget constraints led us to opt for a Verso Q50 instead. One advantage of LDV plates is their ability to be sealed and stored after use, with the option to reuse them if necessary. These LDV intermediate plates, however, require creation using a separate instrument, which can range from cost-effective options like an Apricot to more advanced systems like a Tecan.
For software we started prototyping in KNIME (verso picklists, and echo worklist) and then moved to our own custom solution since we also needed to do direct dilutions.
The Echo (newer one) and other components are integrated into a colab cart that runs on cellario.
