Chromatography Forum

Dear colleagues,

I used TEA in my lcms (ESI -). Now the system ist contaminated by TEA. I already rinsed with isopropanol, buffer, methanol etc. It didn't really help. Especially because TEA makes a strong ion suppression in ESI+ I completely want to eliminate it from the system.
Does anyone has an idea what method works?

Thanks for your help!
Math

You might need to start swapping pieces, and clean the source. Once contaminents become part of the system it can be a real bear to clean them out.

You could start by directly infusing some solvents into the MS and see if the TEA still appears. If not then, the MS can be taken out of the equation. Remove the column, and see about just the plastic lines etc..

Does it appear when the temperature is increased of consistant thoughout the entire run, does it show up as a peak?

Good luck.

TEA can be really tough to get rid of. Have a look at this previous post and the cited paper...

http://chromforum.org/viewtopic.php?t=6 ... ethylamine

Thanks for your comments!
We did the following:
1. Rinse the source with isopropanol, water, 25% nitric acid (15'), water (1,5 h), (of course NOT attached to the ms).

2. according to an advice of the chemist of the manufacturer cleaning of the whole ion path including both quadrupoles

the source seemed then to be clean so far. Nearly no 102-peak.
But the hplc system still produces a peak of > 10^8.

So .....

3. Exchanging all peek-capillaries
4. ultrasonic of the rotor seals in isopropanol
5. Rinse the whole hplc with 25% nitric acid for 15 Minutes
6. Rinse the whole system with water, purge the pulse damper several times
7. Rinse the system one night with 50% isopropanol/water with 0.1% FA

After this procedure, the TEA background went down from originally >2x10^8 to about 10^6. The sensitivity was about half of we are used to, but we can measure already.
One day later, the sensitivity is about what we expect it to be.

So it was a really laborious experience. Fortunately we used this TEA only for about 3 hours.

Thanks a lot!