How do YOU tune/calibrate new compounds on your LC-MS/MS?

[richiekichi]

My employer is considering purchasing a new LC-MS/MS instrument. So we've had a number of manufacturers in giving us their spiel and showing the obligatory 150 million pesticides in 2 seconds chromatogram.

I'm quite a fan of Agilent but I cannot fathom why they insist on tuning/calibrating/optimizing compounds using FIA.

I currently have a couple of Quattro Premiers and although they're a bit of a pain, I reckon tuning/calibrating by infusion is the business. So it seems does every other vendor, except Agilent. I can adjust my source conditions, mobile phase compositions and observe the results of my fiddling. If I so desire I can also have a look at suppression/enhancement by infusing a compound as a I run a sample. These are the practical reasons. There's more than enough evidence to suggest optimization by infusion is the more accurate method too.

I would like to hear about your experiences with tuning/calibrating/optimizing. What methods you use/prefer? Pros/cons? Software? Whatever.

Thanks

[MMJ88]

I've been doing exactly what you describe for the last few days. I am on an Agilent 6410. Agilent does have optimization software, but it hasn't really worked for me. I set up a syringe pump and run straight into the MS with the instrument in manual tune mode. Then it's the usual, I first look at MS2 scan, find my molecular ion (or Na adduct as the case may be ), and optimize for that. Then I lock MS1 on that particular ion and look at MS2 scan while varying the collision energy to find the most promising product ions. Then lock MS2 on that ion and optimize further.

I spent half a day the other day messing with the optimization software (with injections with and without column and direct infusion) to no success (admittedly I have no idea how to use it and no training on it). The next day I did it as described and did all 6 compounds easily.

I'm no expert, but that's just my experience. If you have any other questions about using an Agilent LC/MS/MS setup I'm happy to attempt to answer.

[richiekichi]

Thanks for your reply.

I'm assuming you're using Masshunter? Unfortunately I'm not too familiar with it, so you might have to put with some pretty simplistic questioning.

When you're scanning and optimizing (by infusion) are you still generating data files like you would with FIA? Or is this "Manual Tune Mode" in real-time? You can see your molecular ion on the screen, change the fragmentor voltage, peak goes up or down?

I hope I'm making sense. Agilent just kept telling me I wouldn't need to do any optimizing anyway since I could purchase one of their applications kits for the price of a small wide car.

[MMJ88]

Yep, I'm on masshunter. I am viewing the manual tune in real time as you described and taking notes. There is no data file saved. Perhaps this could present a problem if you need very accurate records of everything? I find it's the fastest way to optimize.

[Pepter]

Hello,
Agilent 6410 and 6460 user here. Iam working with pesticides and mostly use otpimizer software. I dont have syringe pump so i use standard injection option on 4.6x10mm precolumn (connected direct from autosampler to nebulizer). Mostly it takes few minutes to optimize MS parameters for one pesticide (all data recorded).

If you using manual tune maybe simple window recording program (for agilent Webex if i remember good) would be a way to storage your work.