Scheduled tuning of LCMS

Discussions about GC-MS, LC-MS, LC-FTIR, and other "coupled" analytical techniques.

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We've been advised that the scheduled tuning function on our Ultivo TQ should only be used when the TQ has been in operation for a number of hours/days. It should therefore not be used as a 'start-up' tuning function. We've currently set our scheduled checktune for Monday mornings at 6am. The MS has usually been in standby mode before this scheduled checktune is conducted, and it always fail the checktune. Hence the advise that the MS must first 'warm-up'.

I strongly disagree, and would love to know other peoples experience with this function.
You should do what Agilent recommend. I'm guessing that the instrument takes a short while for its electronics to stabilise after it's been started. If you tune it before this has happened, it will find optimum values while it's in an unstable state, and then drift so that these values are no longer optimum.
To be honest, its not really Agilent's advice but the middleman who sold us the equipment. In the brochure for the Ultivo it clearly states that the scheduled tune can be used at the beginning of the work day but also between sample sequences
https://www.agilent.com/cs/library/whit ... gilent.pdf

So I am afraid we got ourselves a cat in the bag with this individual Ultivo (lovely instrument, but ours simply does not seem to work well regarding an extremely variable response to just about any molecule). Mind you, they manufactured this particular MS on the 2nd of January 2020 which may explain our issues.
We have a 6495 and I have found that it definitely needs some time after taking it out of standby before you want to run anything on it. I usually switch it from standby to the method being run and let it run for an hour while I am doing all the other prep for the day before I even attempt to run it. By then all the heated zones have equilibrated, but it sometimes need a couple of standards run before it is completely stable, then it will run all day with no problems.

Just like a fine musical instrument, you don't just take it out of the case and start playing. These are very sensitive instrument and take time to equilibrate when changing temperatures and flows. Patience is a virtue :)
The past is there to guide us into the future, not to dwell in.
Hi, may I ask what the tolerance for check tune are for mass axis and mass width resolution on agilent ultivo system to fail or pass unit resolution test?

Dont really know how accurate mass has to be for a QqQ mrm method. I am thinking it is time when signal for my mrm peaks starts to drop.

If your instrument has variable response from day to day for same concentration this does not seem right for a modern system, it was like this on older systems. Often the brands show data that peak areas vary no more than a few percent over the course of thousands injections. At least waters and sciex show this data and I expect agilent to be at the same level. I would investigate why if it was my instrument and if it is new it is important to find faults when under warranty. Hopefully you only need a bit longer warmup time and not a pcb replacement :lol: . If not resolved I would contact agilent. Make sure that it is not buffer or solvent effect, I get lower signal as my buffer evaporates and this can happen quite fast. When i make new signal is recovered.
Please follow the advice provided. Yes, the system REQUIRES a proper warm up to stabilize after being in stand-by mode (that is why it is called stand-by, not run mode). This is normal. You should not use or run any calibrations UNTIL the system is fully warmed up and stable. The time it takes will vary from system to system because of the settings used and also what types of methods are to be run (programs), sensitivity settings and repeatability levels are expected. Stability is a requirement to use. If you can not attain stability, please call in an experienced user to go over the system (an expert can quickly identify issues). This (waiting for the system to fully stabilize) is something known to regular users and should be part of any training courses for all users.
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