Reminder (Disclaimers --- over there somewhere -->) and never take some weird blogger's opinion of things seriously.
As much as I always feel like typing about an instrument will probably get me in trouble, I guess that hasn't stopped me and I've wanted some hands-on time with one of these things for a long time. And here it is and it's better than I'd ever hoped, even though I realized almost immediately that I completely misunderstood the whole central premise.
Never heard of it? No problem, I'll (probably inaccurately tell you about it!)
What if you weren't allowed to tinker with your flow rates, gradients, or your separation? What if you had a limited set of columns to choose from and each column had a small set of perfectly optimized gradients that come with the instrument when you install it? The team does roll out new methods but people who know enough about HPLC that they can completely design HPLC systems from the ground up do the optimization for you?
I bet this will and does lose some people and customers. Me, personally? I'm dreaming of multiple method sections in papers where instead of looking up my HPLC gradient and poorly describing it, I type "used the vendor 60 SPD method" (its a 22 minute gradient or something, so you can complete 60 total runs in 24 hours).
If your HPLC needs a lot of optimation, like you need to run metabolomics and lipidomics and glycomics on your proteomics HPLC and might require 200 nanoliters/minute for one thing and 500 microliters/minute on others, this might be too limiting. If you're doing proteomics and are tired of everyone yelling at you for your team's gradients always being different lengths on different columns, this is. If you spend a lot of time preaching about reproducibility in proteomics but have a pathological obsession with tweaking settings on instruments and...
Something I didn't understand until Dr. Matt Willetts at Bruker let me look at his system is that -- no autosampler vials or plates ever! You load your samples onto little (probably C-18? tips that can hold [according to something I saw online] something like 1.5 micrograms of peptides. They are like ziptips, but you load them from the top and centrifuge the tips for 1 minute for each step of preparing the tip, loading the sample, and washing the sample). With a microchannel pipettor (now having prepped sample tips around 10 times) it takes me just about the same amount of time to prep 6 samples or 48, which is the most I've prepped at one time so far).
If you do just need to add a QC sample because you're doing an optimization study and things went wonky over the weekend, having a bigger autosampler vial full of your QC sample is more convenient. I think I'm going to try prepping 96 QC samples and then leave the tips in the refrigerator and see how consistent they are as I pull from them over time. Again, a big autosampler vial would probably be easier.
One other intersting thing is the columns that the system uses. They are much shorter and wider than what we're used to! I think the idea is that the peptides are interacting with the same amounts of stationary phase and wider columns last longer. I'm mostly running TMT labeled samples and I care a lot less about chromatography than about getting as many MS2 scans as possible, so I haven't done a thorough (and boring) retention time analysis on it. I really like the 8cm x 150um column, but if I want to use "Whisper" methods (100nanoliter/min) I swap to a more normal 15cm x 75um column.
What else? There is almost no lag time between sample injections once you get going. Maybe a minute or two?
Baseline sensitivity is a bit lower run to run on the normal EvoSep methods than a more traditional HPLC, but I suspect that is entirely because of the higher flowrates (1-2uL/min) than anything else. I bet that is more pronounced for people running 200nL/min.
Final notes -- the tips aren't free. It looks like they're $1.5-$2.50 each depending on how many are purchased at once. Autosampler vials are a lot less expensive, but if I can fully drop cleanup spin columns then this ends up being a dramatic cost savings. Maybe more impressions will follow later, but after 2 weeks and maybe 300 (mostly TMT) samples, it's a great fit for our proteomics projects. Since we do metabolomics, lipidomics, top down, etc., my impression would be very different if there weren't other HPLC systems here.
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