用AxION分析非处方药Melatonin脑白金_褪黑素

1.  Operating the TOF MS in trap (vs. pulse) mode provided a 3 to5 fold improvement in sensitivity. The increased sensitivity allowed additional    impurities  to  be  detected  and  measured  in  an  OTC melatonin sample that were not observed in pulse mode.

2.  The accurate mass measurement capability of the AxION 2 TOF could   easily   distinguished   between   elemental   compositions C14H20N2O3 (m/z = 265.1547) and C13H16N2O4(m/z = 265.1183).

This   provided   the   confirmation   that   a   previously   published structure proposed from data provided by a triple quadrupole MS was incorrect for a specific melatonin impurity.

3.  The significant improvement in sensitivity gained from operating the   AxION TM 2   TOF   in   trap   mode   along   with   the   mass measurement  accuracy  allowed  the  dentification  of  additional melatonin   impurities.   These   included   N1-acetyl-N2-formyl-5-methoxykynurenin  (AFMK)  as  well  as  melatonin  dimers  not observed  in previously published work.