Chromatography Forum

Hi,

I asked this is another thread, but thought I'll post in a new topic to see if anyone else has any comments.

Did anyone, who analyse melamine on LCMSMS, observed polymerization of melamine on the ion spray tip? Is there any way to overcome that?

We have to run a very long sequence to account for instrumental drift, so we are worried about the melamine polymer plugging and clogging the needle tip.

Thanks!

Regards,
Wan

I have done a modest number of samples for melamine & cyanuric acid in food samples using EIS / LC-MS. I never observed any problems attributable to polymerization. It seems somewhat unlikely, unless you are running a large number of highly concentrated samples. Have you actually observed polymerization, or are you worried that it MIGHT occur?

Our samples are typically 20ppb or less in conc. We did observed polymerisation. However, after adjusting the distance of the probe to orifice and adding in more blanks, there is minimal polymerisation.

Wan