Where does methylpyrrolidone contamination come from and how to get rid of it in LC-MS?

We have a huge contaminant at 100.0757 m/z  that we think is methylpyrrolidone [M+H]+. We're using a gradient of MP A: H2O (0.1% Formic acid) and MP B: ACN (0.1%formic acid) on a C18...

11 November 2014 5,628 4 View