Chromatography Forum

Hi!!!
I work with a MSD 5973.
The autotune report shows good MSD parameters.
But the shapes of 69, 219 and 502 ions are not good: their tops are split.
Moreover, the peaks number is high (163).
What is the problem?

Hi!
Your number of peak is o.k.
A dirty source have more than 200 peak...165 peak is not a problem.

Verify that the DC polarity indicate in your autotune report and on your side plate panel of your msd is the same...the optimize dc polarity is manually indicate on this panel...if it is not the same, change it on autotune parameter.
Sometime, when your reset the autotune values, the system change this value.
What is the reppeler voltage?

Hi!
The repeller voltaje is 34.8. Previously it was 28

Astroguille,

Can you post a copy of your profile scan? See directions for posting in the LC section. That gives a tremendous amount of information.

Best regards.

The reppeler is high......the reppeler can be high because it is dirty or maybe, a lens is misaligned or dirty.
1-Verify if your PFTBA vial is not empty
2-Your EM need to be o.k...value below 2600 is the best
3-Clean your source....particularly, the reppeler,the number of peak is o.k. but other information indicate a dirty source
4-Verify the column installation. 1 or 2mm after the end of the interface tube

Try this and good luck

Thanks, but how do I post the copy of my profile scan?

I can't help you for posting...i don't know. Easy way....Send me your autotune report. My email adress is in my profile.

astroguille,

The instructions for posting stuff to the forum can be found as a sticky note near the top of the LC-MS forum.

Best regards.

Thanks everybody

Astroguille,

Oopps, Sorry. Directions for posting to the forum are in a sticky note near the top of the LC forum.

Best regards.