INVESTIGATION OF POTENTIAL DEGRADATION PRODUCTS OF A NEWLY SYNTHESIZED BETA-LACTAM ANTIBIOTIC BY MULTISTAGE LIQUID-CHROMATOGRAPHY ELECTROSPRAY MASS-SPECTROMETRY

This work describes the use of multi-stage liquid chromatography-elect rospray mass spectrometry to characterise four potential degradation p roducts associated with a suspension containing a newly synthesised be ta-lactam antibacterial compound. Initial identification of these degr adates was obtained by analytical LC in which the mobile phase contain ed cetyltrimethylammonium bromide as ion-pairing agent and ammonium ph osphate buffer, both of which are highly involatile making them incomp atible with electrospray mass spectrometry. The use of multi-stage liq uid chromatography maintained the initial LC conditions necessary for the desired separation and at the same time facilitated the use of mas s spectrometry detection. (C) 1998 Elsevier Science B.V. All rights re served.