Chromatography Forum

Dear all,

Recently I run the LC-MS with +ve scan (ESI+APCI) and notice that there is a huge response m/z 282.

I searched related topic in this forum and found some hints (which was posted around 2004)

Is there any further method that I can confirm the m/z belonged to "plasticizer in polyethylene"?

I remebered one team member synthesized a compound with -SiMe3 in it. Would the peak belonged to silica related compound?

And...any web site have info about common LC/MSD contaminants?

Thanks in advance!

Anthony_Ng,

I guess you are referring to this http://en.wikipedia.org/wiki/Oleamide (slipping agent).
Did you use any plastic container with organic solvents?


Instead if you think you have a silicon atom you should see a different isotopic pattern.
Do you have access to a GC-MS? That would be a very easy way to confirm/exclude oleamide.



Regarding the list of common contaminats. The supplier of your MS should be able to help you.

Regards,
bhuvfe

Thanks!

Actually this mass shows everywhere even in basline.

Probably it comes from MeOH. When I switched to other brand, m/z 282 is small but another m/z 339 is very large.

We didn't use plastic ware but use a small glass vial for sample preparation.