1.
Rapid Commun Mass Spectrom
; 12(22): 1820-6, 1998.
Artigo
em Inglês
| MEDLINE
| ID: mdl-9853389
RESUMO
The mass spectrometry (MS) behaviour of ten commercially available penicillins has been studied by means of electrospray and multiple-stage MS/MS experiments performed using an ion trap instrument. For all the examined compounds negative ions are produced under ESI conditions, with a yield two or three orders of magnitude higher than that observed for positive ions. MSn experiments indicate the occurrence of a fragmentation pathway related to the beta-lactam ring, different from that usually described for positive ions of these compounds, and provide structural information on both the beta-lactam ring and the side chains.