By Liyx on Wednesday, August 18, 2004 - 09:00 pm:

My MS (Micromass Ultima) coupled with a Waters HPLC system gave no MS signal when I run LCMS, but the UV chromatogram was OK. When I injected the sample solution through a fusion pump, the MS spectrum could be recorded and the beams were satisfactory in intensity and sensitivity. I cleaned the ionization source and the problem remains.

Can anybody tell me what I should do to obtain the MS chromatogram (TIC)?

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By Bert on Wednesday, August 18, 2004 - 11:45 pm:

Difficult to say. Do you know if your mobile phase is compatible with MS? So, when you infused the sample, was that sample solved in mobile phase? Did you tune your instrument using the analyte solved in the mobile phase?

Regards, Bert

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By ANONY on Thursday, August 19, 2004 - 09:24 am:

The MS software may be hosed up or your using incorrect tuning files.

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By Anonaswell on Friday, August 20, 2004 - 05:31 am:

i) Is there a steady spray out of your Z-Spray probe when you're running from the LC?
ii) What's the flow rate from your LC (same as from the syringe?)
iii) Check the tune file that's selected from the sample list.