Study on the Behavior of Valnemulin in Electrospray Ionization Mass Spectrometry

The fragmentation behavior of Valnemulin was studied in both positive and negative ion mode by electrospray ionization mass spectrometry. The results indicate that the intensity of molecular ion peak M+H⁺ is m/z 565.7 in positive ion mode, and M-H^- is m/z 563.5 in negative ion mode, which response is lower than the former. Then, the M+H⁺ is cracked with suitable collision energy in the MS². The main fragment ions include m/z 263.2, 285.3， 303.3, and the intensity of m/z 263.2 is maximal. This method can be applied for the further research, such as structure-function relationship, pharmaceutical and residual analysis, etc.