Investigation of unknown related substances in commercial neomycin samples with liquid chromatography/ion trap tandem mass spectrometry.
The characterization of unknown impurities present in neomycin sulfate by liquid chromatography (LC) coupled with ion trap mass spectrometry (ITMS) is described. The volatile LC method was developed using an evaporative light scattering detector due to its lower investment and operating costs, easier operation and less maintenance than mass spectrometry. The method shows separation of neomycin B from seven potential related substances reported in the European Pharmacopoeia and several other unknown impurities. The unknown impurities were further investigated by coupling the developed LC method with ITMS. Their structures were deduced based on the fragmentation patterns obtained from reference substances. Four unknowns were identified as isomers of paromamine, LP-A, neamine and LP-B.
Li
Bo
B
Laboratorium voor Farmaceutische Analyse, Faculteit Farmaceutische Wetenschappen, Katholieke Universiteit Leuven, O&N2, PB 923, Herestraat 49, B-3000 Leuven, Belgium.
Van Schepdael
Ann
A
Hoogmartens
Jos
J
Adams
Erwin
E
D000900:Anti-Bacterial Agents / Q000032:analysis*; D002853:Chromatography, Liquid; D004340:Drug Contamination; D007202:Indicators and Reagents; D009355:Neomycin / Q000032:analysis*; D012015:Reference Standards; D021241:Spectrometry, Mass, Electrospray Ionization; D053719:Tandem Mass Spectrometry
D000900:Anti-Bacterial Agents; D007202:Indicators and Reagents; D009355:Neomycin