Chromatography Forum

Hi all,

In my 5973 atune report, sometimes the peak of 219 is splitted. Everything else is normal. Anyone know what is that problem and may it do any harms to analyses?

Thanks for reading.

Hi!

Can you put the autotune report in this post?

Hi!

Can you put the autotune report in this post?

All the parameters are normal. I will scan the tune report later. This is just an illustration.

It sometimes happens in my instrument too. It doesn't really hurt. You may either narrow the peak width of m/z 219 before tuning or clean the ion source. It may help.

Hello, I'm curious to know if you figured out the split peaks issue on the tune.

I'm having the same issue. Source cleaning does not fix it. we clean the source about every 2 months. We run urine extracts on the instrument, hundreds per week, and with it being 6 years old now, I'm wondering if the quads themselves are dirty?

I can back down the repeller to help reduce and sometimes remove the splitting, but the high end response takes a huge hit, which is a big negative for our THC metabolite extracts.

So did you ever get it fixed?

Some detectors give a split peak when they saturate ( the signal is too high).
Compare the counts for 219 to the counts for the other peaks you use in tune. Is the peak for 219 the highest?
If so, you might try a slight dilution.

Alp

We've seen this a lot! Both in EI and in CI with ammonia gas. We've found that exhaustively cleaning the source can help, as can lowering the repeller voltage (our analytes tend to be at the lower end of the mass range, so it doesn't hurt us to do that). Another way to help it is to change the polarity of the quads.
Hope this helps. I will echo, though, that unless you have a very tight mass calibration spec, the split peak doesn't seem to hurt things very much.

Clean the END of the quads (source end).