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- Posts: 88
- Joined: Mon May 16, 2016 11:50 am
Im using a second "clean" pump to spray IPA on MS which is very useful as it removes the triton and peg ions after a few minutes, so I can keep troubleshooting.
When I reconnect the "contaminated" pump, I immediately see 505 ion, so I have to disconnect and flush with IPA again from clean pump.
Ive flushed LC only overnight with 50% meoh, 25% ACN 15% cyclohexane and 10% DCM to waste. I still see issues.
I have run from bad pump out directly (bypassing CTC sampler) to MS with lines A and C and its clean. But lines B and D show the contaminated ions immediately
Im replacing all MP lines on Monday.
Any suggestions? Flushing LC with warm water? B and D are common for ACN so i wonder if poorly washed bottle was culprit.
I also see phthalates and polysiloxane ions. This is better than triton and PEG, my question is: Is it normal to see Phthalates (plastics from MP lines) and polysiloxanes (glass bottle) when scanning? The MS has to see "something" right?
COuld Nitrogen gas line be an issue?
thanks alot
source:https://projects.ncsu.edu/ncsu/chemistry/msf/pdf/Contaminants_PositiveMode_MS.pdf