Hi all,

We have a very large contaminant ion m/z107 & m/z108 on 6430 LC/MS/MS. It's not from the LC because I have use the tune bottle containing acetonitrile and the peaks are still there. It's strange that with MeOH or Water, the peaks are almost gone. I have replace new acetonitrile and peaks again appear !
Could anyone ever have this problem ?
Thanks for any help.