I am using star and vantage. yes its beads vs columns
Adding to this - I actually wrote many of the Prep scripts and they are bead-based rather than column-based which may matter depending on your preference. Plasmid NAP workflows vary greatly depending on broth and species and can sometimes create a āgoopā after lysis and before binding which can be difficult to automate. At Omega, we also tested using MPE2 on STAR and had a few collaborations with EVO units with Te-Vacs which all worked great, but thereās just a lot of variability in what settings to use for those systems that youāll need to test for yourself. Bead-based NAP is certainly better suited for porting and distributing to different platforms with minimal tweaking.
In summary, the homework you need to do is testing to find ideal optical density to begin extraction, sample format leading to bead- or column-friendly workflows, and sample/broth combo and how it reacts to lysis chemistry. After that, the Bind/Wash/Elute is easy regardless of NAP method. One final thing about bead-based extractions, but this protocol is typically very tip-usage heavy since there are many supernatant removals and steps where sample is physically in contact with tip, which can add to cost depending on your favorite tip vendor.
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Resurrecting from the dead here - did you manage to solve your issue? I spent a few years developing and optimizing an MPE-based workflow for plasmid preps which just wrapped up. We managed to get ~10-15ug yield from a 2mL culture, and were able to run 2x96W plates in about 1h15m. Lots of troubleshooting and very satisfying to get it to work!
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Hello Keith,
Thanks for the message. I am really interested in learning more about it. can u please let me know more details either here or please email me.
Thanks,
Kalpesh
Please put the details here, Iād like to see them too!
Glad thereās interest! While I was working on it, the company I was working for had a few people say āOh, 2 x 96W plate in an hour? The [XYZ sales rep] said they have a [XYZ robot] that can do that out of the boxā, which makes it seem trivial. Any other option they explored turned out to be low yield, or slower than promised, or high RNA contamination (often the problem with bead-based methods).
We used the Macherey-Nagel kit, thereās a white paper of their method that they released with Hamilton which we based off of and made a number of modifications.
Some issues we faced and solved:
We custom printed a few different adapters to be able to nest the filter plates with each other. This avoided a step which required moving a filter plate full of liquid from below the MPE adapter to above it, which would almost invariably result in some dripping/loss of liquid and potential cross-contamination. Also dripping salty buffers on the MPE railing would result in corrosion.
The salty buffers didnāt behave nicely with the MPE waste system - causing the ball valve in the waste line to seize up and the MPE vacuum system to fail to initialize. We printed special reservoir troughs to catch and collect the waste instead.
The MPE library is very particular with respect to states and the ability to process selected steps. If anything at all went wrong and an MPE step failed (this is regular from our experience), the method would need to be aborted and samples would not be able to be recovered. I wrote an intermediate library for the MPEs that would catch these errors and give users the ability to remediate them without aborting the method. This was crucial.
We tested a whole range of parameters for time and pressure for clearing buffers through the filter plates - I even went so far as to read up on droplet dispensing physics to try and balance between A) High pressure for too much time caused spraying out of the nozzle and generation of aerosols/cross contamination potential, as well as bubbles in the sample, and B) low pressure would cause a lot of hanging droplets/incomplete clearance of liquid, resulting in reduced yield and the same droplets on rails/into the output plate issues as above.
There was a lot of troubleshooting to get it going but as I said, very satisfying to complete after 4.5 years.
If you would like to share what issues you are running into specifically, I would be happy to offer some advice 
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