Tuning trouble for dftpp on a 5973

[a2j812]

I've got a very sick 5973. I cannot get an autotune or a dftpp tune to complete. There is some issue with the 502 ion. The peak shape is very jagged, and the responses are minimal. I know the source is clean. Its been cleaned several times. I have restored the tune files to defaults, and tried old tune files and it still cannot achieve a stable peak width.
Any thoughts?

[willnatalie]

How did you clean the source?

[a2j812]

Polished with Wenol, sonicated, and baked.

[willnatalie]

First I would not clean with Wenol and I would not bake it out. The sheen that Wenol would give could cause issues with the MSD.

Have you cleaned it this way before and got it to work?

What I do
take silica oxide and water to make a paste - scrub each component with a cotton tipped applicator till the dark spots are gone and the metal has a nice shine to it.

soniqate in DI water a few times for about 15-20 minutes each
soniqate in acetone a few times for about 15-20 minutes each
soniqate in MeOH a few times for about 15-20 minutes each

after this wear gloves and place the components back together and back into the MS. Give it some time half a day to a day to remove all the air and water while HE is flowing and then tune.

[a2j812]

Yes, we clean all our sources this way, and never had an issue. The problem arose when we took the door off of a working 5973 and placed it on a 5973 that was giving us a few issues. So the one that was working is now giving us problems, and the one that was giving us problems is now working on the other MS, so I don't think its necessarily the source that is giving us the problem.

[willnatalie]

The door of the MSD that holds all the components not on the GC?

[AICMM]

a2j812,

Dead EM? What was the last EM voltage you had on an autotune that worked?

Best regards,

AICMM

[a2j812]

Willnatalie,
YEs, the door from the MSD that holds all the components.

AICMM,
It's possible that the EM is dead. I'll try to scrounge up another one to replace it. I think the last EM Voltage on a good autotune was between 1400 and 1500.

[willnatalie]

try swapping out just the source components (in a complete set).

Have you ramped any of the lenses and the repeller? This can give you information about lose connections, and the repeller will let you know if the source still has problems.

Are you have any pressure issues with either one?

When you do figure it out let me know. I'm interested to know what was wrong.

[a2j812]

Well, I guess we'll never get to the bottom of this mystery. We ended up purchasing a new MS, and after resetting the ATUNE parameters I finally got a good auto tune. I then saved the ATUNE file as the DFTPP file, and was able to get a DFTPP tune to pass. (I had done that with the old MS too, but it didn't help.)
I'd like to thank you all for all of your valuable help.

[JI2002]

Hoe did you reset the atune parameters?

[a2j812]

We use Agilent ChemStation & EnviroQuant, but if you go into the MANUAL TUNE screen, under the FILE menu, there an option to RESET TO DEFAULTS. If you click that, it asks you which tune file you want to bring back to default. Select the ATUNE file, and click OK.

[JI2002]

I use a 5975 MSD, I don't have the "reset to defaults" option under the file menu. Your technique is something I haven't seen before. So what's the reason for setting the ATUNE to defaults? What do you do after that?

[a2j812]

What version of the ChemStation software are you using? This was on an older version. The one that is compatible with a 5975 is a little different. Mine is running at the moment so I can't access it.

I reset the ATUNE file because our tune files had been adjusted so much in order to try to get it to work, that they no longer resembled anything that would pass a DFTPP. After I got the ATUNE to pass (by resetting the file), I knew that if I used those parameters for the DFTPP tune, it would likely pass.
When my 5975 stops running, I'll see if I can find how to reset the tune file parameters.

[Bigbear]

You are correct, the newer versions of chemstation have no "reset to default" option. We have found that the tune files can get corrupted and will not work. This seems to happen when you keep overwriting the same file name. If you use a manual tune try saving it to a method /date name so that each one is unique.

There is a folder in chemstation where there are "fresh" tune files. Call the 800 number for help in re setting your tune files. I can't remember all the steps.