I performed LC-MS/MS measurements by injecting my samples on nano liquid chromatography system (nanoACQUITYy, Waters, Manchester, UK) coupled via ESI to a quadrupole-orbitrap mass spectrometer (Orbitrap QExcactive, Thermo Scientific, Bremen, Germany).I noticed a message:system over pressure.Here I attached a photo of the problem.Why this arise?and how I can solve it?
Hi Eric,
First of all: what is the pressure alarm limit you've set in the method you're running?
Other than that, nanoLC is quite infamous for the fact that it is prone to clogging: so after injecting a sample that contains just the smallest particle, your pre-column (or analytical column) can get clogged, resulting in high pressure due to obstruction of the system.
The way to overcome this is to replace the pre-column, flush and start over again (reset the pump) and to make sure that the samples you're injecting are absolutely particle-free (for example by centrifuging them prior to analysis).
Just to be sure that the nanoLC is causing the problem (the spray needle of the Thermo source could also be clogged), you can decouple the nanoLC from the MS and see whether the problem persists.
Hope this helps!
- Badges
- Science topic
- Similar topics
- Chemistry
- Nanotechnology
- Nano